A novel role of Krüppel-like factor 4 in Zhikong scallop Chlamys farreri during spermatogenesis

• Published in: PloS one Vol. 12; no. 6; p. e0180351
• Main Authors: Yang, Dandan, Zhang, Zhifeng, Liang, Shaoshuai, Yang, Qiankun, Wang, Yingrui, Qin, Zhenkui
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 30.06.2017; Public Library of Science (PLoS)
• Subjects: Amino Acid Sequence; Animals; Apoptosis; Biology and Life Sciences; Cell cycle; Deoxyribonucleic acid; Differentiation; DNA; DNA, Complementary; Education; Epithelial cells; Females; Gametes; Genes; Genetics; Gonads; Histology; Immunohistochemistry; Interference; KLF4 protein; Kruppel-Like Transcription Factors - chemistry; Kruppel-Like Transcription Factors - genetics; Kruppel-Like Transcription Factors - physiology; Laboratories; Male; Males; Mammals; Medicine and Health Sciences; Oogenesis; Ovaries; Pectinidae; Pluripotency; Polymerase chain reaction; Real time; Retardance; Ribonucleic acid; RNA; RNA Interference; RNA-mediated interference; Rodents; Scallops; Sequence Homology, Amino Acid; Sex reversal; Shellfish; Somatic cells; Spermatocytes; Spermatogenesis; Spermatogenesis - physiology; Spermatozoa; Studies; Testes; Transcription factors; Zinc; Zinc finger proteins; China
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0180351

Krüppel-like factor 4 (KLF4) is a kind of zinc finger transcription factor, which is involved in terminal differentiation of epithelial cells and reprogramming of somatic cells to induced pluripotent stem (iPS) cells in mammals. In the present study, we identified a full-length cDNA of Klf4 in Zhikong scallop Chamys farreri (Cf-Klf4) and found that Cf-Klf4 presented a sexual dimorphic expression characteristic in C. farreri gonads. Cf-Klf4 expression was significantly higher in testes than in ovaries from growing stage to mature stage detected by quantitative real-time PCR, and was located in male gametes, except for spermatozoa during spermatogenesis through in situ hybridization and immunohistochemistry, while no positive signal was visible in female gametes during oogenesis. Furthermore, the knockdown of Cf-Klf4 in testes by means of in vivo RNA interference led to an obviously developmental retardance, lower gonadosomatic index, less male gametes and more apoptotic spermatocytes. Interestingly, we found that two out of eight scallops showed a hermaphroditic phenotype characteristic of male-to-female sex reversal when the Klf4 mRNA and protein levels were knocked down in males. These results verified that Klf4 plays an important role in testis functional maintenance and is necessary in spermatogenesis of C. farreri.