{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T15:15:22Z","timestamp":1789398922331,"version":"build-2803163510"},"reference-count":35,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,25]],"date-time":"2022-12-25T00:00:00Z","timestamp":1671926400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Shandong Province Natural Fund Project","award":["ZR2020MC168"],"award-info":[{"award-number":["ZR2020MC168"]}]},{"name":"Shandong Province Natural Fund Project","award":["SDAIT-27"],"award-info":[{"award-number":["SDAIT-27"]}]},{"name":"Shandong Province Natural Fund Project","award":["19211162"],"award-info":[{"award-number":["19211162"]}]},{"name":"Shandong Province Natural Fund Project","award":["2021TZXD012"],"award-info":[{"award-number":["2021TZXD012"]}]},{"name":"Shandong Province Modern Agricultural Industrial Technology System Project","award":["ZR2020MC168"],"award-info":[{"award-number":["ZR2020MC168"]}]},{"name":"Shandong Province Modern Agricultural Industrial Technology System Project","award":["SDAIT-27"],"award-info":[{"award-number":["SDAIT-27"]}]},{"name":"Shandong Province Modern Agricultural Industrial Technology System Project","award":["19211162"],"award-info":[{"award-number":["19211162"]}]},{"name":"Shandong Province Modern Agricultural Industrial Technology System Project","award":["2021TZXD012"],"award-info":[{"award-number":["2021TZXD012"]}]},{"name":"Construction of Molecular ID Card for Donkey and Camel Species, Livestock and Poultry Seed Industry Project of Ministry of Agriculture and Rural Affair","award":["ZR2020MC168"],"award-info":[{"award-number":["ZR2020MC168"]}]},{"name":"Construction of Molecular ID Card for Donkey and Camel Species, Livestock and Poultry Seed Industry Project of Ministry of Agriculture and Rural Affair","award":["SDAIT-27"],"award-info":[{"award-number":["SDAIT-27"]}]},{"name":"Construction of Molecular ID Card for Donkey and Camel Species, Livestock and Poultry Seed Industry Project of Ministry of Agriculture and Rural Affair","award":["19211162"],"award-info":[{"award-number":["19211162"]}]},{"name":"Construction of Molecular ID Card for Donkey and Camel Species, Livestock and Poultry Seed Industry Project of Ministry of Agriculture and Rural Affair","award":["2021TZXD012"],"award-info":[{"award-number":["2021TZXD012"]}]},{"name":"Key R&amp;D Project of Shandong Province: Innovation and Demonstration of Key Technologies for the Integrated Development of Donga Black Donkey Industry","award":["ZR2020MC168"],"award-info":[{"award-number":["ZR2020MC168"]}]},{"name":"Key R&amp;D Project of Shandong Province: Innovation and Demonstration of Key Technologies for the Integrated Development of Donga Black Donkey Industry","award":["SDAIT-27"],"award-info":[{"award-number":["SDAIT-27"]}]},{"name":"Key R&amp;D Project of Shandong Province: Innovation and Demonstration of Key Technologies for the Integrated Development of Donga Black Donkey Industry","award":["19211162"],"award-info":[{"award-number":["19211162"]}]},{"name":"Key R&amp;D Project of Shandong Province: Innovation and Demonstration of Key Technologies for the Integrated Development of Donga Black Donkey Industry","award":["2021TZXD012"],"award-info":[{"award-number":["2021TZXD012"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Circular RNAs (circRNAs) are a class of noncoding RNAs with a covalently closed loop. Studies have demonstrated that circRNA can function as microRNA (miRNA) sponges or competing endogenous RNAs. Although circRNA has been explored in some species and tissues, the genetic basis of testis development and spermatogenesis in donkeys remain unknown. We performed RNA-seq to detect circRNA expression profiles of adult donkey testes. Length distribution and other characteristics were shown a total of 1971 circRNAs were differentially expressed and 12,648 and 6261 circRNAs were detected from the testis and caput epididymis, respectively. Among these circRNAs, 1472 circRNAs were downregulated and 499 circRNAs were upregulated in the testis. Moreover, KEGG pathway analyses and Gene Ontology were performed for host genes of circRNAs. A total of 39 upregulated circRNA host genes were annotated in spermatogenesis terms, including PIWIL2, CATSPERD, CATSPERB, SPATA6, and SYCP1. Other host genes were annotated in the focal adhesion, Rap1 signaling pathway. Downregulated expressed circRNA host genes participated in the TGF-\u03b2 signaling pathway, GnRH signaling pathway, estrogen signaling pathway, and calcium signaling pathway. Our discoveries provide a solid foundation for identifying and characterizing critical circRNAs involved in testis development or spermatogenesis.<\/jats:p>","DOI":"10.3390\/genes14010066","type":"journal-article","created":{"date-parts":[[2022,12,27]],"date-time":"2022-12-27T07:02:12Z","timestamp":1672124532000},"page":"66","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Identification of Circular RNAs of Testis and Caput Epididymis and Prediction of Their Potential Functional Roles in Donkeys"],"prefix":"10.3390","volume":"14","author":[{"given":"Yan","family":"Sun","sequence":"first","affiliation":[{"name":"Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Technology, Shandong Agricultural University, Taian 271018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yonghui","family":"Wang","sequence":"additional","affiliation":[{"name":"Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng 252059, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuhua","family":"Li","sequence":"additional","affiliation":[{"name":"Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng 252059, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Faheem","family":"Akhtar","sequence":"additional","affiliation":[{"name":"Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng 252059, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5186-1703","authenticated-orcid":false,"given":"Changfa","family":"Wang","sequence":"additional","affiliation":[{"name":"Liaocheng Research Institute of Donkey High-Efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng 252059, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qin","family":"Zhang","sequence":"additional","affiliation":[{"name":"Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Technology, Shandong Agricultural University, Taian 271018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"103885","DOI":"10.1016\/j.livsci.2019.103885","article-title":"Integrated analysis of mRNA and miRNA in testis and cauda epididymidis reveals candidate molecular markers associated with reproduction in Dezhou donkey","volume":"234","author":"Tian","year":"2020","journal-title":"Livestock Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1038\/nature11928","article-title":"Circular RNAs are a large class of animal RNAs with regulatory potency","volume":"495","author":"Memczak","year":"2013","journal-title":"Nature"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"e63","DOI":"10.1093\/nar\/gkl151","article-title":"Characterization of RNase R-digested cellular RNA source that consists of lariat and circular RNAs from pre-mRNA splicing","volume":"34","author":"Suzuki","year":"2006","journal-title":"Nucleic Acids Res."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"256","DOI":"10.1038\/nsmb.2959","article-title":"Exon-intron circular RNAs regulate transcription in the nucleus","volume":"22","author":"Li","year":"2015","journal-title":"Nat. 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