Identification of some unknown transcripts from SSH cDNA library of buffalo follicular oocytes

Abstract

A buffalo oocyte-specific subtracted cDNA library was constructed to identify exclusively or preferentially oocyte-expressed genes. The library represented an enriched population of transcripts obtained from oocytes of diverse ovarian follicular origin and at different stages of in vitro maturation. A total of 1173 high-quality sequences of oocyte-specific genes were clustered into 645 unique sequences, out of which 65.76% were represented as singlets and 34.26% as contig expressed sequence tags (ESTs; clusters). Analysis of sequences revealed that 498 of these sequences were identified as a known sequence in mammalian species including buffalo, 103 as uncharacterized ESTs and 44 unknown sequences including 1 novel EST, so far not reported in any species. Gene ontology annotation classified these sequences into functional categories of cellular events and biological processes associated with oocyte competence. Expression status of the isolated unknown ESTs confirmed that many of these are expressed in oocytes exclusively and in others preferentially, some in excess of 80-fold greater in comparison with a variety of somatic tissues. The isolated novel EST was detected to be expressed exclusively in oocytes and testicular cells only. To our knowledge, this is the first report giving a detailed transcriptome account of oocyte-expressed genes in buffalo. This study will provide important information on the physiological control of oocyte development, as well as many questions yet to be addressed on the reproductive process of buffalo.

Polymorphism of JY-1 gene is not associated with reproductive traits in goats

“…Therefore, Bettegowda et al [1] concluded that the oocyte-specific JY-1 protein is most likely species-specific. Contrary to this view, Rajput et al [3] had reported expression of JY-1 in buffaloes where polymorphisms, including insertion of a thymine, were detected in the coding region (exon 3). This insertion causes a frameshift mutation, modifying the 19 terminal amino acids of the buffalo protein and creating a premature stop codon [4].…”

Identification of the JY‐1 in sika deer and its effects on granulosa cells cultured in vitro

“…A previous study reported that the first specific maternally derived protein was discovered in the exon sequence of the JY-1 in Zebu cattle and buffalo, which are single-ovulating species (de Camargo, Baldi, Regitano, & Tonhati, 2013). Rajput identified the bovine JY-1 gene as an specific gene in preimplantation embryo development (Rajput et al, 2013). The bovine JY-1 gene consists of three exons: 25, 92 and 1,400 bp, corresponding to the first, second and third exons, respectively (Bettegowda et al, 2007).…”

First-Time Characterization of <i>JY-1</i>-Like Sequence in Goats

“…Therefore, Bettegowda et al (2007) concluded that the oocyte-specific JY-1 protein is probably species specific. Incidentally, Rajput et al (2013) recently identified expression of JY-1 in buffaloes and reported polymorphisms, including insertion of a thymine in the codifying region of exon 3 of the buffalo sequence. This insertion causes a frameshift mutation, modifying the 19 terminal amino acids of the buffalo protein and creating a premature stop codon (de Camargo et al, 2013).…”