{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T17:09:45Z","timestamp":1772557785935,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2016,5,18]],"date-time":"2016-05-18T00:00:00Z","timestamp":1463529600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The epidermis is an important tissue in Homo sapines and other animals, and an abnormal epidermis will cause many diseases. Phosphatase 2A (PP2A) is an important serine and threonine phosphatase. The \u03b1 isoform of the PP2A catalytic subunit (Ppp2ca gene encoding PP2Ac\u03b1) is critical for cell proliferation, growth, metabolism and tumorigenesis. However, to date, no study has revealed its roles in epidermis development. To specifically investigate the roles of PP2Ac\u03b1 in epidermis development, we first generated Ppp2caflox\/flox transgenic mice, and conditionally knocked out Ppp2ca in the epidermis driven by Krt14-Cre. Our study showed that Ppp2caflox\/flox; Krt14-Cre mice had significant hair loss. In addition, histological analyses showed that the morphogenesis and hair regeneration cycle of hair follicles were disrupted in these mice. Moreover, Ppp2caflox\/flox; Krt14-Cre mice had smaller size, melanin deposition and hyperproliferation at the base of the claws. Accordingly, our study demonstrates that PP2Ac\u03b1 plays important roles in both hair follicle and epidermis development. Additionally, the Ppp2caflox\/flox mice generated in this study can serve as a useful transgene model to study the roles of PP2Ac\u03b1 in other developmental processes and diseases.<\/jats:p>","DOI":"10.3390\/ijms17050756","type":"journal-article","created":{"date-parts":[[2016,5,18]],"date-time":"2016-05-18T10:10:24Z","timestamp":1463566224000},"page":"756","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Conditional Knockout in Mice Reveals the Critical Roles of Ppp2ca in Epidermis Development"],"prefix":"10.3390","volume":"17","author":[{"given":"Chao","family":"Fang","sequence":"first","affiliation":[{"name":"Department of Pharmacology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing 210029, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lei","family":"Li","sequence":"additional","affiliation":[{"name":"Translational Medicine Center, Yancheng No. 1 People\u2019s Hospital, Yancheng 224000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jianmin","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing 210029, China"},{"name":"Model Animal Research Center of Nanjing Medical University, Nanjing 210029, China"},{"name":"Key Laboratory of National Reproductive Medicine Department of Cell Biology and Medical Genetics, Nanjing Medical University, Nanjing 210029, China"},{"name":"Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Nanjing Medical University Nanjing, Nanjing 210029, China"},{"name":"Department of cell biology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing 210029, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,5,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10869","DOI":"10.3390\/ijms140610869","article-title":"Epidermal development in mammals: Key regulators, signals from beneath, and stem cells","volume":"14","author":"Liu","year":"2013","journal-title":"Int. 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