Major chimpanzee-specific structural changes in sperm development-associated genes
A comprehensive analysis of transcriptional structures of chimpanzee sperm development-associated genes is of significant interest for deeply understanding sperm development and male reproductive process. In this study, we sequenced 7,680 clones from a chimpanzee testis full-length cDNA library and obtained 1,933 nonredundant high-quality full-length cDNA sequences. Comparative analysis between human and chimpanzee showed that 78 sperm development-associated genes, most of which were yet uncharacterized, had undergone severe structural changes (mutations at the start/stop codons, INDELs, alternative splicing variations and fusion forms) on genomic and transcript levels throughout chimpanzee evolution. Specifically, among the 78 sperm development-associated genes, 39 including ODF2, UBC, and CD59 showed markedly chimpanzee-specific structural changes. Through dN/dS analysis, we found that 56 transcripts (including seven sperm development-associated genes) had values of greater than one when comparing human and chimpanzee DNA sequences, whereas the values were less than one when comparing humans and orangutans. Gene ontology annotation and expression profiling showed that the chimpanzee testis transcriptome was enriched with genes that are associated with chimpanzee male germ cell development. Taken together, our study provides the first comprehensive molecular evidence that many chimpanzee sperm development-associated genes had experienced severe structural changes over the course of evolution on genomic and transcript levels.
KeywordsStructural changes Chimpanzee Testis Sperm development Gene ontology
We thank the members of the Genome Resource Center (GRC) at the Korea Research Institute of Bioscience and Biotechnology (KRIBB) for their excellent screening and sequencing work. This research was supported by grant 2007-04269 from the Ministry of Education, Science and Technology and grant KGM1230812 from the Korea Research Institute of Bioscience and Biotechnology (KRIBB).
- Hughes JF, Skaletsky H, Pyntikova T, Graves TA, van Daalen SK, Minx PJ, Fulton RS, McGrath SD, Locke DP, Friedman C, Trask BJ, Mardis ER, Warren WC, Repping S, Rozen S, Wilson RK, Page DC (2010) Chimpanzee and human Y chromosomes are remarkably divergent in structure and gene content. Nature 463(7280):536–539PubMedCrossRefGoogle Scholar
- Kuroki Y, Toyoda A, Noguchi H, Taylor TD, Itoh T, Kim DS, Kim DW, Choi SH, Kim IC, Choi HH, Kim YS, Satta Y, Saitou N, Yamada T, Morishita S, Hattori M, Sakaki Y, Park HS, Fujiyama A (2006) Comparative analysis of chimpanzee and human Y chromosomes unveils complex evolutionary pathway. Nat Genet 38(2):158–167PubMedCrossRefGoogle Scholar
- Lovejoy CO (2009) Reexamining human origins in light of Ardipithecus ramidus. Science 326(5949):74e71–74e78Google Scholar
- Saifuddin M, Hedayati T, Atkinson JP, Holguin MH, Parker CJ, Spear GT (1997) Human immunodeficiency virus type 1 incorporates both glycosyl phosphatidylinositol-anchored CD55 and CD59 and integral membrane CD46 at levels that protect from complement-mediated destruction. J Gen Virol 78(Pt 8):1907–1911PubMedGoogle Scholar