{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T02:56:26Z","timestamp":1791082586195,"version":"4.1.0"},"reference-count":67,"publisher":"Oxford University Press (OUP)","issue":"9","license":[{"start":{"date-parts":[[2019,7,22]],"date-time":"2019-07-22T00:00:00Z","timestamp":1563753600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"funder":[{"name":"National Transgenic Creature Breeding Grand Project","award":["2016ZX08008-005"],"award-info":[{"award-number":["2016ZX08008-005"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2019,9,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>Spermatogonial stem cells (SSCs) self-renew and contribute genetic information to the next generation. Pig is wildly used as a model animal for understanding reproduction mechanisms of human being. Inducing directional differentiation of porcine SSCs may be an important strategy in exploring the mechanisms of spermatogenesis and developing better treatment methods for male infertility. Here, we established an in-vitro culture model for porcine small seminiferous tubule segments, to induce SSCs to differentiate into single-tail haploid spermatozoa. The culture model subsequently enabled spermatozoa to express the sperm-specific protein acrosin and oocytes to develop to blastocyst stage after round spermatid injection. The addition of retinoic acid (RA) to the differentiation media promoted the efficiency of haploid differentiation. RT-PCR analysis indicated that RA stimulated the expression of Stra8 but reduced the expression of NANOS2 in spermatogonia. Genes involved in post-meiotic development, transition protein 1 (Tnp1) and protamine 1 (Prm1) were upregulated in the presence of RA. The addition of an RA receptor (RAR) inhibitor, BMS439, showed that RA enhanced the expression of cAMP responsive-element binding protein through RAR and promoted the formation of round spermatids. We established an efficient culture system for in-vitro differentiation of pig SSCs. Our study represents a model for human testis disease and toxicology screening. Molecular regulators of SSC differentiation revealed in this study might provide a therapeutic strategy for male infertility.<\/jats:p>","DOI":"10.1093\/molehr\/gaz043","type":"journal-article","created":{"date-parts":[[2019,7,13]],"date-time":"2019-07-13T07:08:49Z","timestamp":1563001729000},"page":"507-518","source":"Crossref","is-referenced-by-count":13,"title":["In-vitro differentiation of early pig spermatogenic cells to haploid germ cells"],"prefix":"10.1093","volume":"25","author":[{"given":"Kun","family":"Yu","sequence":"first","affiliation":[{"name":"Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Haidian District, Beijing, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi","family":"Zhang","sequence":"additional","affiliation":[{"name":"CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Chaoyang District, Beijing, People\u2019s Republic of China"},{"name":"Department of Medicine, Panzhihua University, Sichuan, Sichuan, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bao-Lu","family":"Zhang","sequence":"additional","affiliation":[{"name":"Marine Consulting Center of MNR, Oceanic Counseling Center, Ministry of Natural Resources of the People's Republic of China, Feng-tai District, Beijing, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Han-Yu","family":"Wu","sequence":"additional","affiliation":[{"name":"Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Haidian District, Beijing, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wu-Qi","family":"Jiang","sequence":"additional","affiliation":[{"name":"Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Haidian District, Beijing, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Su-Tian","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Animal Science and Technology, Northeast Agricultural University, Harbin, Xiangfang District, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"De-Ping","family":"Han","sequence":"additional","affiliation":[{"name":"Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Haidian District, Beijing, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi-Xun","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8511-9673","authenticated-orcid":false,"given":"Zheng-Xing","family":"Lian","sequence":"additional","affiliation":[{"name":"Beijing Key Laboratory for Animal Genetic Improvement, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics and Breeding of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Haidian District, Beijing, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1187-3037","authenticated-orcid":false,"given":"Shou-Long","family":"Deng","sequence":"additional","affiliation":[{"name":"CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Chaoyang District, Beijing, People\u2019s Republic of China"},{"name":"State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, People\u2019s Republic of China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2019,7,22]]},"reference":[{"key":"2019102107390745700_ref1","doi-asserted-by":"crossref","first-page":"7657","DOI":"10.1128\/MCB.25.17.7657-7664.2005","article-title":"Reduction of spermatogenesis but not fertility in Creb3l4-deficient mice","volume":"25","author":"Adham","year":"2005","journal-title":"Mol Cell Biol"},{"key":"2019102107390745700_ref2","doi-asserted-by":"crossref","first-page":"229","DOI":"10.1016\/j.ydbio.2017.10.002","article-title":"Retinoic acid deficiency leads to an increase in spermatogonial stem number in the neonatal mouse testis, but excess retinoic acid results in no change","volume":"432","author":"Agrimson","year":"2017","journal-title":"Dev Biol"},{"key":"2019102107390745700_ref3","doi-asserted-by":"crossref","first-page":"154","DOI":"10.1016\/j.theriogenology.2017.10.041","article-title":"Characterization of domestic pig spermatogenesis using spermatogonial stem cell markers in the early months of life","volume":"107","author":"Almunia","year":"2018","journal-title":"Theriogenology"},{"key":"2019102107390745700_ref4","doi-asserted-by":"crossref","first-page":"14976","DOI":"10.1073\/pnas.0807297105","article-title":"Stra8 and its inducer, retinoic acid, regulate meiotic initiation in both spermatogenesis and oogenesis in mice","volume":"105","author":"Anderson","year":"2008","journal-title":"Proc Natl Acad Sci U S A"},{"key":"2019102107390745700_ref5","doi-asserted-by":"crossref","first-page":"709","DOI":"10.1071\/RD05126","article-title":"In vitro effects of epidermal growth factor, follicle stimulating hormone and testosterone on mouse spermatogonial cell colony formation","volume":"18","author":"Anjamrooz","year":"2006","journal-title":"Reprod Fertil Dev"},{"key":"2019102107390745700_ref6","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1186\/s40104-017-0222-0","article-title":"Optimization of culture conditions for short-term maintenance, proliferation, and colony formation of porcine gonocytes","volume":"9","author":"Awang-Junaidi","year":"2018","journal-title":"J Anim Sci Biotechnol"},{"key":"2019102107390745700_ref7","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1111\/j.1439-0272.2009.00960.x","article-title":"SCF and c-kit expression profiles in male individuals with normal and impaired spermatogenesis","volume":"42","author":"Bialas","year":"2010","journal-title":"Andrologia"},{"key":"2019102107390745700_ref8","doi-asserted-by":"crossref","first-page":"140","DOI":"10.1016\/j.ydbio.2014.10.020","article-title":"Retinoic acid regulates Kit translation during spermatogonial differentiation in the mouse","volume":"397","author":"Busada","year":"2015","journal-title":"Dev Biol"},{"key":"2019102107390745700_ref9","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1095\/biolreprod.115.135145","article-title":"The role of retinoic acid (RA) in spermatogonial 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