Correspondence to Edith Hummler: Edith.Hummler{at}unil.ch
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I. Rubera's present address is Laboratoire de Physiologie Cellulaire et Moléculaire, Université de Nice Sophia-Antipolis, 06108 Nice, Cedex 2, France.
M. Guitard's present address is Cutaneous Biology Research Center, Charlestown, MA 02129.
Abbreviations used in this article: CAP, channel-activating protease; ENaC, epithelial sodium channel; GPI, glycosyl-phosphatidylinositol; K, keratin; LSM, laser scanning microscopy; MT-SP1, membrane-type serine protease 1; Prss8, protease serine S1 family member 8; SC, stratum corneum; SG, stratum granulosum; TEWL, transepidermal water loss; TJ, tight junction.
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Introduction |
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We recently isolated channel-activating protease (CAP) 1 (also termed protease serine S1 family member 8 [Prss8]), which presents the mouse homologue of the human prostasin. CAP1/Prss8 is found in various mammalian tissues like semen, the prostate gland, and skin (Vuagniaux et al., 2000). The physiological role of this protein is largely unknown, although a deregulation of Prss8 expression is found in high-grade human prostate, breast, and ovarian cancers (Takahashi et al., 2003; Chen et al., 2004). Further roles of this serine protease have been proposed for cellular growth, morphogenesis, and sodium absorption in the kidney and lung (for review see Rossier, 2004).
Skin is the largest organ of the human body, and it functions primarily as a barrier to the physical environment by the skin's relative impermeability to water, water-soluble compounds, and pathogenic micro-organisms. The constant thickness of the epidermis is maintained by a balance between the proliferation of keratinocytes in the basal layer and desquamation from the surface of the stratum corneum (SC). When this process is altered, xerotic and ichthyotic conditions may arise (Pierard et al., 2000). In skin, proteinases and protease inhibitors like gelatinase A, nexin-1, or SC chymotryptic enzyme regulate hair growth and/ or cycling (Ekholm and Egelrud, 1998; Sonoda et al., 1999; Karelina et al., 2000). Mice that are deficient for the papainlike lysosomal cystein protease cathepsin L exhibit structural changes of hair follicles and altered epidermal differentiation (Benavides et al., 2002).
Here, we study the consequences of CAP1/Prss8 deficiency in epidermal function. These mice died early after birth as a result of severe dehydration, thus demonstrating the involvement of CAP1/Prss8 in the epidermal barrier function that is indispensable for postnatal survival.
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Results |
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Early postnatal lethality and skin abnormalities in mice lacking CAP1 in the epidermis
Genotype analysis of newborn offspring revealed a ratio that was consistent with the Mendelian pattern of inheritance (Fig. 2 a, left). However, when a total of 119 animals from 10 litters were genotyped at the weaning age, we could not detect Prss8lox//K14-Cre animals (Fig. 2 a, right). This was further investigated by monitoring 56 pups (n = 4 litters) during 72 h after birth (Fig. 2 b). None of the 18 genotyped epidermis-specific CAP1/Prss8 knockouts was found alive >60 h after birth, demonstrating that CAP1/Prss8 expression in skin is indispensable for early postnatal survival.
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Impairment of the epidermal barrier function
Next, we tested the functional integrity of the epidermis by measuring the inwards and outwards barrier function. As illustrated in Fig. 3 a, knockout mice severely lost more weight than their littermates (10% in 6 h vs. 23% in the control group), which is interpreted as liquid loss by evaporation through the skin. Increased dehydration was further confirmed in these mice by measuring the transepidermal water loss (TEWL), which increased by almost 40% in neonates from the knockout group (Fig. 3 b). These mice also showed increased toluidine blue penetration across the entire epidermal surface and more especially at the ventral side, whereas controls were completely unstained (Fig. 3 c). This severe impairment of both inwards and outwards barrier functions of the epidermis in knockout animals strongly suggests the involvement of CAP1/Prss8 in epidermal barrier function.
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Discussion |
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Identification of the molecular nature of the barrier is still under investigation, with the consensus that a protein lipid layer, which is located in the top layers of the epidermis and TJs, plays an essential role in development of the skin barrier function (Tsuruta et al., 2002). Evidence that cornified envelope assembly is necessary for barrier development in skin is obtained from the study of transglutaminase 1deficient mice that lack confirmed envelopes. These mice suffer from water loss, resulting in neonatal lethality (Matsuki et al., 1998). Alterations of corneocyte morphology have also been described in various mouse models with epidermal permeability barrier defects ranging from near absence in transglutaminase 1deficient mice (Matsuki et al., 1998) to irregular shaped corneocytes (e.g., Klf4/ mice; Segre et al., 1999). Our corneocyte phenotype mostly resembled that of matriptase/MT-SP1deficient mice, a member of the type II transmembrane serine protease family (List et al., 2003). Equally, mice with a targeted disruption of Fatp4 (fatty acid transport protein 4) showed a disturbed fatty acid composition of epidermal ceramides with a normal distribution of TJ proteins (Herrmann et al., 2003), although a functional TJ assay has not been performed. In the CAP1/Prss8-deficient epidermis, the level of barrier-forming lipids with very long chain fatty acids that were covalently attached to proteins was significantly reduced, suggesting a potential cause for the observed defect in epidermal barrier permeability (Fig. 4). These barrier lipids were formed by mice only a few days before birth (Doering et al., 2002), and their deficiency in prosaposin- and ß-glucocerebrosidase knockout mice resulted in disruption of the water permeability barrier and in early death (Doering et al., 1999a,b). Interestingly, the observed imbalance in ceramide composition did not result from an altered keratinocyte differentiation, as epidermal differentiation markers (K14, K1, involucrin, loricrin, and filaggrin) seemed not to be affected (Fig. 6). Defective profilaggrin to filaggrin processing, as seen in the CAP1/Prss8 knockout group, may lead to abnormal SC hydration, which further results in the downstream depletion of humectant amino acids and their deiminated products (Fig. 5; Elias, 2004; for review see Rawlings and Harding, 2004). At the transition between the granular layer and SC, the processing of profilaggrin, which consists of multiple filaggrin repeats joined by linker peptides, involves dephosphorylation and proteolytic steps through three-domain and two-domain intermediates to filaggrin (Fig. 5; Resing et al., 1984). According to the proposed consensus site for proteolytic cleavage by CAP1 (Shipway et al., 2004), two preferred polybasic cleavage sites are situated within filaggrin, thus suggesting a mechanism for CAP1 activation.
Moreover, TJs are important for barrier function (Furuse et al., 2002), indicating that two systems for forming a barrier exist in skin. Indeed, CAP1/Prss8-deficient mice exhibited an altered composition of lipids, precursors, and defective filaggrin processing but also exhibited an impaired function of TJ, thus leading to a severely compromised epidermal permeability barrier that likely accounted for early neonatal death. Interestingly, the link between protease action and TJ disruption has been made by the treatment of epithelial cell lines with Derp1, a cysteine protease that reversibly disrupts TJs (Wan et al., 1999). Apparently, Derp1 acts to increase paracellular permeability by direct proteolytic cleavage of occludin and possibly claudin. This proteolysis is assumed to cause the breakdown of the TJ protein complex. In CAP1/Prss8-deficient epidermis, occludin seems to be absent from these TJs despite the normal presence of claudin-1 and ZO-1 (Fig. 7 a). Interestingly, mice lacking occludin show a complex phenotype, and the TJs themselves are not affected morphologically and functionally (Saitou et al., 2000). By sequence comparison, we found a CAP1-preferred polybasic cleavage site in ZO-1 but not in occludin protein, suggesting that the mechanism of protease action on occludin may be indirect (unpublished data). Nevertheless, the diffusion of injected biotinylation reagent was not prevented, suggesting that the assembly of TJ proteins to functional units is crucial. Thus, the TJ complex may not be that different from wild-type mice, as supported by claudin-1 and occludin-deficient mice (Saitou et al., 2000; Furuse et al., 2002).
The physiological role of most of the membrane-anchored serine proteases is still unclear, and the endogenous targets of the majority of these enzymes have not been identified. Matriptase/MT-SP1 has been proposed to initiate signaling and proteolytic cascades through its ability to activate cell surfaceassociated proteins like pro-uPA and PAR-2, although an inappropriate processing of these substrates might not contribute to the epidermal phenotype of matriptase/MT-SPIdeficient mice (Takeuchi et al., 2000; List et al., 2002). In vitro and in vivo experiments indicated that membrane-bound serine proteases may be of importance in the activation of the highly amiloride-sensitive sodium channel ENaC (Rossier, 2004). These serine proteases include Prss8 (CAP1 or prostasin), TMPRSS4 (CAP2), matriptase/MT-SP1 (epithin or CAP3), and TMPRSS3 (Vallet et al., 1997; Vuagniaux et al., 2000, 2002; Guipponi et al., 2002). As evidenced by RNA and protein analyses, ENaC subunits are expressed in keratinocytes, whereas the dermis is negative (Brouard et al., 1999). Interestingly, ENaC and CAP1/Prss8 mRNA transcript expression was found in nondifferentiated keratinocytes (Oda et al., 1999) and increased 2.2-fold in more differentiated keratinocytes, as evidenced by real-time PCR (unpublished data). In extracellular domains of the
and ß subunits of ENaC, CAP1-preferred polybasic cleavage sites were recently found, suggesting a direct interaction with this protease (Shipway et al., 2004). Therefore, ENaC may present a potential substrate for CAP1 (Hughey et al., 2003, 2004), although it is unlikely that ENaC is the only substrate of CAP1. Newborn mice, in which ENaC activity had been deleted, demonstrated epithelial hyperplasia, abnormal nuclei, premature secretion of lipids, and abnormal expression of differentiation markers. This finding suggests that this channel modulates ionic signaling for specific aspects of epidermal differentiation, such as synthesis or processing of differentiation-specific proteins, and lipid secretion (Mauro et al., 2002). It will be interesting to analyze TJs in these knockout mice. Membrane-bound serine proteases might exhibit pleiotropic functions in the activation of growth factors or G proteincoupled receptors and in the activation of proteolytic cascades. A comparison of the skin phenotypes of CAP1/Prss8- with matriptase/MT-SP1deficient mice indeed suggests that both serine proteases may participate in the same protease-signaling cascade.
In humans, defective epidermal barrier function is seen in a variety of skin disorders that are generally presumed to be ichthyosis. Interestingly, the phenotype of our epidermis CAP1/Prss8-deficient mice strikingly resembles a severe form of congenital ichthyosis, the harlequin disease. Harlequin ichthyosis is an autosomal recessive human disorder affecting skin cornification, and affected infants often die within days to weeks of birth, apparently as a result of massive hyperkeratosis and/ or a severe epidermal permeability barrier defect (for review see Dale and Kam, 1993). A "harlequin-like" mouse showed mutations in cystatin M/E, which is a serine protease inhibitor and substrate for transglutaminase, but no gene mutations have been identified so far in harlequin ichthyosis patients (Zeeuwen et al., 2003). Recently, analysis of a pig-a epidermis-specific knockout mouse suggested that defective GPI-anchored proteins may account for harlequin ichthyosis (types I and II) in humans (Hara-Chikuma et al., 2004). Although the X-linked pig-a gene has been excluded, CAP1/Prss8 may represent a candidate gene for this disease. This study may facilitate further analysis of the role of this membrane-anchored serine protease in normal skin development, the identification of putative target proteins, and its implication in genetic disorders.
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Materials and methods |
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Genotyping was performed by using DNA-based PCR analysis from biopsies (tail and organs) and was analyzed by PCR using the following three primers: Prss8 sense, A (5'-GCAGTTGTAAGCTGTCATGTG-3'); Prss8 sense, B (5'-CAGCAGCTGAGGTACCACT-3'); and Prss8 antisense, C (5'-CCAGGAAGCATAGGTAGAAG-3') to detect Prss8 wild-type (379 bp), lox- (413 bp), and -specific (473 bp) PCR-amplified products. 36 cycles were run, each consisting of 1 min at 94, 56, and 72°C. The presence of the Cre transgene was detected by PCR using Cre-specific primers (sense, 5'-CCTGGAAAATGCTTCTGTCCG-3'; and antisense, 5'-CAGGGTGTTATAAGCAATCCC-3') to amplify a 350-bp fragment (36 cycles were run as described above). Myogenin-specific primers (sense, 5'-TTACGTCCATCGTGGACAGC-3'; and antisense, 5'-TGGGCTGGGTGTTAGTCTTA-3') were used to control the DNA integrity of each sample.
For reverse transcription PCR, total RNA was isolated, extracted from newborn mouse tissues (RNeasy Mini Kit; QIAGEN), and reverse transcribed (Superscript II; Invitrogen) as described previously (Olivier et al., 2002). PCR amplification was performed with primers situated in exons 4 and 6 of Prss8 (exon 4 sense, F [5'-CAGCCAATGCCTCCTTTCCC-3']; and exon 6 antisense, G [5'-TCACCCCAACTCACAATGCC-3']). 40 cycles (each consisting of 1 min at 95, 57, and 72°C) were run to amplify a Prss8-specific mRNA fragment of 309 bp. GAPDH primers (sense, 5'-CGTCTTCACCACCATGGAGA-3'; and antisense, 5'-CGGCCATCACGCCACAGTTT-3') were used as loading controls. Amplified PCR products were separated on a 2% agarose gel and were visualized by ethidium bromide staining.
Histopathological analysis and immunohistochemistry
For complete histopathological analysis, whole newborn litters from knockout and control groups were fixed overnight in 4.5% phosphate-buffered formalin, pH 7, and were embedded in paraffin. 4-µm sagittal sections were stained with hematoxylin and eosin and were examined by light microscopy using a photomicroscope (Axioplan; Carl Zeiss MicroImaging, Inc.). Images were acquired with a high sensibility digital color camera (AxionHRc; Carl Zeiss MicroImaging, Inc.).
Immunohistochemistry was performed on newborn skin samples that were frozen in optimum cutting temperature compound (Sakura Finetek). Affinity-purified CAP1/Prss8 rabbit antiserum (Planes et al., 2005) was incubated for 1 h at RT on 10-µm cryosections that were previously fixed for 10 min in 4% PFA. Staining was visualized by laser scanning microscopy (LSM) with a confocal microscope (model LSM510 Meta; Carl Zeiss MicroImaging, Inc.) after 45 min of incubation at RT with CY3 antirabbit IgG (Jackson ImmunoResearch Laboratories). Mouse antibodies to K6 (clone Ks6.KA12; Progen Biotechnik GmbH), K14, K1, involucrin, loricrin, and filaggrin were purchased from Covance and were used at a dilution of 1:1,000 except for K14 (1:4,000).
Antibodies against TJ proteins.
Rabbit anticlaudin-1 pAb (Zymed Laboratories) was used (1:100 dilution) in combination with CY3 antirabbit IgG (Jackson ImmunoResearch Laboratories). mAb antioccludin (MOC37) and ZO-1 (T8-754) were provided by M. Furuse (Kyoto University, Kyoto, Japan) and were combined with FITC-conjugated antimouse antibodies (Calbiochem). After fixation (30 min in 95% ethanol at 4°C and 1 min in acetone at RT) and permeabilization (10 min in 0.2% Triton X-100/PBS), the incubation of cryosections with primary antibody was performed overnight at 4°C after blocking 30 min in PBS/3% BSA, and the reaction was revealed with secondary antibody for 2 h at 4°C. Nuclei were counterstained with 0.2 µg/ml DAPI in mounting medium.
Epidermal protein extraction and Western blot analysis
The epidermis and dermis were separated by heating the skin for 5 min at 54°C in 5 mM EDTA/PBS. Then, the epidermis was homogenized in ice-cold 1 M NaSCN, 50 mM Hepes, 10 mM EDTA, pH 6.8, 0.3 mM orthophenantroline, 20 µg/ml PMSF, and 0.1% isopropanol (Resing et al., 1984), and the lysate was cleared by centrifugation at 12,000 g for 15 min at 0°C after adding 10 vol of ice-cold water. 50 µg of proteins were separated by SDS-PAGE on 416% acrylamide gradient gels. Antibodies were detected with donkey antirabbit IgG at a dilution 1:10,000 (GE Healthcare), and the signal was developed with the Supersignal West Dura System (Pierce Chemical Co.). Western blot analysis was performed by using rabbit antibodies to filaggrin (1:1,000; Covance), loricrin (1:1,000), K1 (1:1,000), K14 (1:10,000), and involucrin (1:1,000).
Lipid analysis
Whole skin from newborns were removed at autopsy, frozen, and stored at 20°C until further treatment. SC preparation, lipid analysis, and recovery/analysis of covalently bound lipids was performed as described previously (Reichelt et al., 2004).
Functional analyses of the epidermal barrier
Skin permeability assay.
Newborn mice from knockout and control groups were killed and subjected to methanol dehydration and subsequent rehydration as described previously (Koch et al., 2000). They were further washed in PBS, stained overnight at 4°C in 0.1% toluidine blue/PBS (Merck), destained in PBS, and photographed with a digital camera (Coolpix 950; Nikon; List et al., 2002).
Measurement of TEWL.
The rate of TEWL from the ventral skin of newborn mice was determined by using a Tewameter (Courage and Khazaka) as described previously (Barel and Clarys, 1995; Matsuki et al., 1998).
Dehydration assay.
To determine the rate of fluid loss (List et al., 2002), newborns from three independent litters were separated from their mother to prevent fluid intake, and the rate of epithelial water loss was calculated by measuring the reduction of body weight as a function of time.
TJ permeability assay.
A TJ functional test was performed according to methods developed previously (Chen et al., 1997) and was adapted for skin (Furuse et al., 2002). 30 min after injection, the skin was dissected out and frozen in optimum cutting temperature compound (Tissue-Tek). About 10-µm-thick sections were fixed as described previously (Furuse et al., 2002). Staining was visualized by an LSM confocal microscope after the incubation of sections with streptavidin AlexaFluor488 (Invitrogen) overnight at 4°C. Three wild-type and four knockout mice were independently analyzed for this experiment.
Calculations and statistics
All data are expressed as means ± SEM. Values of n refer to the number of mice in each group. Individual groups were compared by using the t test for all pair-wise comparisons. A level of P 0.05 was accepted as statistically significant for all comparisons.
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Acknowledgments |
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This work was supported by the Swiss National Science Foundation (grants 31-063801.00 and 3100A0-102125/1 to E. Hummler).
Submitted: 7 January 2005
Accepted: 21 June 2005
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References |
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Barel, A.O., and P. Clarys. 1995. Study of the stratum corneum barrier function by transepidermal water loss measurements: comparison between two commercial instruments: Evaporimeter and Tewameter. Skin Pharmacol. 8:186195.[Medline]
Benavides, F., M.F. Starost, M. Flores, I.B. Gimenez-Conti, J.-L. Guénet, and C.J. Conti. 2002. Impaired hair follicle morphogenesis and cycling with abnormal epidermal differentiation in nackt mice, a cathepsin L-deficient mutation. Am. J. Pathol. 161:693703.
Brandner, J.M., S. Kief, C. Grund, M. Rendl, P. Houdek, C. Kuhn, E. Tschachler, W.W. Franke, and I. Moll. 2002. Organization and formation of the tight junction system in human epidermis and cultured keratinocytes. Eur. J. Cell Biol. 81:253263.[Medline]
Brouard, M., M. Casado, S. Djelidi, Y. Barrandon, and N. Farman. 1999. Epithelial sodium channel in human epidermal keratinocytes: expression of its subunits and relation to sodium transport and differentiation. J. Cell Sci. 112:33433352.
Chen, L.M., X. Zhang, and K.X. Chai. 2004. Regulation of prostasin expression and function in the prostate. Prostate. 59:112.[CrossRef][Medline]
Chen, Y.-H., C. Merzdorf, D.L. Paul, and D.A. Goodenough. 1997. COOH terminus of occludin is required for tight junction barrier function in early Xenopus embryos. J. Cell Biol. 138:891899.
Doering, T., W.M. Holleran, A. Potratz, G. Vielhaber, P.M. Elias, K. Suzuki, and K. Sandhoff. 1999a. Sphingolipid activator proteins are required for epidermal permeability barrier function. J. Biol. Chem. 274:1103811045.
Doering, T., R.L. Proia, and K. Sandhoff. 1999b. Accumulation of protein-bound epidermal glucosylceramides in beta-glucocerebrosidase-deficient type 2 Gaucher mice. FEBS Lett. 447:167170.[CrossRef][Medline]
Doering, T., H. Brade, and K. Sandhoff. 2002. Sphingolipid metabolism during epidermal barrier development in mice. J. Lipid Res. 43:17271733.
Dale, B.A., and E. Kam. 1993. Harlequin ichthyosis. Variability in expression and hypothesis for disease mechanism. Arch. Dermatol. 129:14711477.[Abstract]
Ekholm, E., and T. Egelrud. 1998. The expression of stratum corneum chymotrypsic enzyme in human anagen hair follicles: further evidence for its involvement in desquamation-like processes. Br. J. Dermatol. 139:585590.[CrossRef][Medline]
Elias, P.M. 2004. The epidermal permeability barrier: from the early days at Harvard to emerging concepts. J. Invest. Dermatol. 122:xxxvixxxix.[CrossRef][Medline]
Furuse, M., M. Hata, K. Furuse, Y. Yoshida, A. Haratake, Y. Sugitani, T. Noda, A. Kubo, and S. Tsukita. 2002. Claudin-based tight junctions are crucial for the mammalian epidermal barrier: a lesson from claudin-1deficient mice. J. Cell Biol. 156:10991111.
Guipponi, M., G. Vuagniaux, M. Wattenhofer, K. Shibuya, M. Vazquez, L. Dougherty, N. Scamuffa, E. Guida, M. Okui, and C. Rossier, et al. 2002. The transmembrane serine protease (TMPRSS3) mutated in deafness DFNB8/10 activates the epithelial sodium channel (ENaC) in vitro. Hum. Mol. Genet. 11:28292836.
Hara-Chikuma, M., J. Takeda, M. Tarutani, Y. Uschida, W.M. Holleran, Y. Endo, P.M. Elias, and S. Inoue. 2004. Epidermal-specific defect of GPI anchor in pig-a null mice results in harlequin ichthyosis-like features. J. Invest. Dermatol. 123:464469.[CrossRef][Medline]
Herrmann, T., F. Van der Hoeven, H.-J. Gröne, A.F. Stewart, L. Langbein, I. Kaiser, G. Liebisch, I. Gosch, F. Buchkremer, and W. Drobnik, et al. 2003. Mice with targeted disruption of the fatty acid transport protein 4 (Fatp 4, Slc27a4) gene show features of lethal restrictive dermopathy. J. Cell Biol. 161:11051115.
Hughey, R.P., G.M. Mueller, J.B. Bruns, C.L. Kinlough, P.A. Poland, K.L. Harkleroad, M.D. Carattino, and T.R. Kleyman. 2003. Maturation of the epithelial Na+ channel involves proteolytic processing of the alpha- and gamma-subunits. J. Biol. Chem. 278:3707337082.
Hughey, R.P., J.B. Bruns, C.L. Kinlough, K.L. Harkleroad, Q. Tong, M.D. Carattino, J.P. Johnson, J.D. Stockand, and T.R. Kleyman. 2004. Epithelial sodium channels are activated by furin-dependent proteolysis. J. Biol. Chem. 279:1811118114.
Karelina, T.V., G.A. Bannikov, and A.Z. Eisen. 2000. Basement membrane zone remodeling during appendageal development in human fetal skin. The absence of type VII collagen is associated with gelatinase-A (MMP2) activity. J. Invest. Dermatol. 114:371375.[CrossRef][Medline]
Kinoshita, T., N. Inoue, and J. Takeda. 1995. Defective glycosyl phosphatidylinositol anchor synthesis and paroxysmal nocturnal hemoglobinuria. Adv. Immunol. 60:57103.[Medline]
Koch, P.J., P.A. de Viragh, E. Scharer, D. Bundman, M.A. Longley, J. Bickenbach, Y. Kawachi, Y. Suga, Z. Zhou, and M. Huber, et al. 2000. Lessons from loricrin-deficient mice: compensatory mechanisms maintaining skin barrier function in the absence of a major cornified envelope protein. J. Cell Biol. 151:389400.
Lakso, M., J.G. Pichel, J.R. Gorman, B. Sauer, Y. Okamoto, E. Lee, F.W. Alt, and H. Westphal. 1996. Efficient in vivo manipulation of mouse genomic sequences at the zygote stage. Proc. Natl. Acad. Sci. USA. 93:58605865.
Li, M., H. Chiba, X. Warot, N. Messaddeq, C. Gerard, P. Chambon, and D. Metzger. 2001. RXT-alpha ablation in skin keratinocytes results in alopecia and epidermal alterations. Development. 128:675688.
List, K., C.C. Haudenschild, R. Szabo, W. Chen, S.M. Wahl, W. Swaim, L.H. Engelholm, N. Behrendt, and T.H. Bugge. 2002. Matriptase/MT-SP1 is required for postnatal survival, epidermal barrier function, hair follicle development, and thymic homeostasis. Oncogene. 21:37653779.[CrossRef][Medline]
List, K., R. Szabo, P.W. Wertz, J. Segre, C.C. Haudenschild, S.-Y. Kim, and T.H. Bugge. 2003. Loss of proteolytically processed filaggrin caused by epidermal deletion of matriptase/MT-SP1. J. Cell Biol. 163:901910.
Macheleidt, O., H.W. Kaiser, and K. Sandhoff. 2002. Deficiency of epidermal protein-bound omega-hydroxyceramides in atopic dermatitis. J. Invest. Dermatol. 119:166173.[CrossRef][Medline]
Matsuki, M., F. Ymashita, A. Ishida-Yamamoto, K. Yamada, C. Kinoshita, S. Fushiki, E. Ueda, Y. Morishima, K. Tabata, and H. Yasuno, et al. 1998. Defective stratum corneum and early neonatal death in mice lacking the gene for transglutaminase 1(keratinocyte transglutaminase). Proc. Natl. Acad. Sci. USA. 95:10441049.
Mauro, T., M. Guitard, Y. Oda, D. Crumrine, L. Komuves, M. Behne, U. Rassner, P.M. Elias, and E. Hummler. 2002. The ENaC channel is required for normal epidermal differentiation. J. Invest. Dermatol. 118:589594.[CrossRef][Medline]
Netzel-Arnett, S., J.D. Hooper, R. Szabo, E.L. Madison, J.P. Quigley, T.H. Bugge, and T.M. Antalis. 2003. Membrane anchored serine proteases: a rapidly expanding group of cell surface proteolytic enzymes with potential roles in cancer. Cancer Metastasis Rev. 22:237258.[CrossRef][Medline]
Oda, Y., A. Imanzahrei, A. Kwong, L. Komuves, P.M. Elias, C. Largman, and T. Mauro. 1999. Epithelial sodium channel are upregulated during epidermal differentiation. J. Invest. Dermatol. 113:796801.[CrossRef][Medline]
Olivier, R., U. Scherrer, J.-D. Horisberger, B.C. Rossier, and E. Hummler. 2002. Selected contribution: limiting Na(+) transport rate in airway epithelia from alpha-ENaC transgenic mice: a model for pulmonary edema. J. Appl. Physiol. 93:18811887.
Pearton, D.J., W. Nirunsuksiri, A. Rehemtulla, W.P. Lewis, R.B. Presland, and B.A. Dale. 2001. Proprotein convertase expression and localization in epidermis: evidence for multiple roles and substrates. Exp. Dermatol. 10:193203.[CrossRef][Medline]
Pierard, G.E., V. Goffin, T. Hermanns-Le, and C. Pierard-Franchimont. 2000. Corneocyte desquamation. Int. J. Mol. Med. 6:217221.[Medline]
Planes, C., C. Leyvraz, T. Uchida, M.A. Angelova, G. Vuagniaux, E. Hummler, M. Matthay, C. Clerici, and B.C. Rossier. 2005. In vitro and in vivo regulation of transepithelial lung alveolar sodium transport by serine proteases. Am. J. Physiol. Lung Cell. Mol. Physiol. 288:L1099L1109.
Rawlings, A.V., and C.R. Harding. 2004. Moisturization and skin barrier function. Dermatol. Ther. 17:4348.[CrossRef][Medline]
Reichelt, J., B. Breiden, K. Sandhoff, and T.M. Magin. 2004. Loss of keratin 10 is accompanied by increased sebocyte proliferation and differentiation. Eur. J. Cell Biol. 83:747759.[Medline]
Resing, K.A., K.A. Walsh, and B.A. Dale. 1984. Identification of two intermediates during processing of profilaggrin to filaggrin in neonatal mouse epidermis. J. Cell Biol. 99:13721378.[Abstract]
Resing, K.A., C. Thulin, K. Whiting, N. Al-Alawi, and S. Mostad. 1995. Characterization of profilaggrin endoproteinase 1. J. Biol. Chem. 270:2819328198.
Rossier, B.C. 2004. The epithelial sodium channel: activation by membrane-bound serine proteases. Proc. Am. Thorac. Soc. 1:49.
Rubera, I., E. Meier, G. Vuagniaux, A.-M. Mérillat, F. Beermann, B.C. Rossier, and E. Hummler. 2002. A conditional allele at the mouse channel activating protease 1 (Prss8) gene locus. Genesis. 32:173176.[CrossRef][Medline]
Saitou, M., M. Furuse, H. Sasaki, J.-D. Schulzke, M. Fromm, H. Takano, T. Noda, and S. Tsukita. 2000. Complex phenotype of mice lacking occludin, a component of tight junction strands. Mol. Biol. Cell. 11:41314142.
Segre, J. 2003. Complex redundancy to build a simple epidermal permeability barrier. Curr. Opin. Cell Biol. 15:776782.[CrossRef][Medline]
Segre, J.A., C. Bauer, and E. Fuchs. 1999. Klf4 is a transcription factor required for establishing the barrier function of the skin. Nat. Genet. 22:356360.[CrossRef][Medline]
Shipway, A. H. Danahay, J.A. Williams, D.C. Tully, B.J. Backes, and J.L. Harris. 2004. Biochemical characterization of prostasin, a channel activating protease. Biochem. Biophys. Comm. 324:953963.[CrossRef][Medline]
Sonoda, T., Y. Asada, S. Kurata, and S. Takayasu. 1999. The mRNA for protease nexin-1 is expressed in human dermal papilla cells and its level is affected by androgen. J. Invest. Dermatol. 113:308313.[CrossRef][Medline]
Takahashi, S., S. Suzuki, S. Inaguma, Y. Ikeda, Y.-M. Cho, N. Hayashi, T. Inoue, Y. Sugimura, N. Nishiyama, and T. Fujita, et al. 2003. Down-regulated expression of prostasin in high-grade or hormone-refractory human prostate cancers. Prostate. 54:187193.[CrossRef][Medline]
Takeuchi, T., J.L. Harris, W. Huang, K.W. Yan, S.R. Coughlin, and C.S. Craik. 2000. Cellular localization of membrane-type serine protease I and identification of protease-activated receptor-2 and single-chain urokinase-type plasminogen activator as substrates. J. Biol. Chem. 275:2633326342.
Tsuruta, D., K.J. Green, S. Getsios, and C.R. Jones. 2002. The barrier function of skin: how to keep a tight lid on water loss. Trends Cell Biol. 12:355357.[CrossRef][Medline]
Vallet, V., A. Chraibi, H.-P. Gaeggeler, J.-D. Horisberger, and B.C. Rossier. 1997. An epithelial serine protease activates the amiloride-sensitive sodium channel. Nature. 389:607610.[CrossRef][Medline]
Vuagniaux, G., V. Vallet, N. Jaeger-Fowler, M. Bens, N. Farman, N. Courtois-Coutry, A. Vandewalle, B.C. Rossier, and E. Hummler. 2000. Activation of the amiloride-sensitive epithelial sodium channel by the serine protease mCAP1 expressed in a mouse cortical collecting duct cell line. J. Am. Soc. Nephrol. 11:828834.
Vuagniaux, G., V. Vallet, N.F. Jaeger, E. Hummler, and B.C. Rossier. 2002. Synergistic activation of ENaC by three membrane-bound channel activating serine proteases (mCAP1, mCAP2 and mCAP3) and serum- and glucocorticoid-regulated kinase (Sgk1) in Xenopus oocytes. J. Gen. Physiol. 120:191201.
Wan, H., H.L. Winton, C. Soeller, E.R. Tovey, D.C. Gruenert, P.J. Thompson, G.A. Stewart, G.A. Taylor, D.R. Garrod, M.B. Cannell, and C. Robinson. 1999. Der p 1 facilitates transepithelial allergen delivery by disruption of tight junctions. J. Clin. Invest. 104:123133.
Yamazaki, M., K. Ishidoh, Y. Suga, T.C. Saido, S. Kawashima, K. Suzuki, E. Kominami, and H. Ogawa. 1997. Cytoplasmic processing of human profilaggrin by active mu-calpain. Biochem. Biophys. Res. Commun. 235:652656.[CrossRef][Medline]
Zeeuwen, P.L.J.M., B.A. Dale, G.J. de Jongh, I.M.J.J. Van Vlijmen-Willems, P. Fleckman, J.R. Kimball, K. Stephens, and J. Schalkwijk. 2003. The human cystatin M/E gene (CST6): exclusion candidate gene for harlequin ichthyosis. J. Invest. Dermatol. 121:6568.[CrossRef][Medline]
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