Structure and expression of ovarian connexin Je-Cx34.4 and Je-Cx43 in Japanese eel (Anguilla japonica)
Date Issued
2015
Date
2015
Author(s)
Liao, Wei-Ning
Abstract
Gap junctions (GJs), composed of connexin (Cx) protein subunits, allow direct communication through conduits between neighboring cells in vertebrate. From teleost to mammals, throughout oogenesis, cell-cell communication via GJs between oocytes and surrounding follicle cells, and/or amongst follicle cells is required for successful follicular development. However, the functions and regulation of ovarian GJs or Cx during earlier stages of oogenesis, such as previtellogenic and vitellogenic stages, mostly remain to explored. To gain a fundamental understanding of ovarian GJs in teleost, we identified 7 Cx genes in our Japanese eel (Anguilla japonica) ovarian cDNA library. One of the gene transcripts designated Je-Cx34.4 were confirmed by polymerase chain reaction (PCR); In addition, Cx43, a highly conserve Cx gene in vertebrates could retrieve partial sequence through PCR with degenerated primers from ovary cDNA, we designated Je-Cx43. Tissue distribution showed that Je-Cx34.4 was only expressed in ovary, by contrast Je-Cx43 were at least expressed in six tissues. Phylogenetic analysis shows that Je-Cx34.4 may be the Cx subfamily only in teleost; Je-Cx43 was similar to other species Cx43, especially. To study early oogenesis of Japanese eel, fish received weekly intraperitoneal injections of salmon pituitary extracts (SPE). Ovarian tissue were sample weekly and gonadosomatic index (GSI%) was used as an ovary development status. Changes in gene expression across the early oogenesis were determined by using quantitative real-time PCR (qPCR). Transcription of Je-Cx34.4 was not different during every week of induction, same results seem in Je-Cx43. Although transcript of Je-Cx34.4 increase in induction group, but was not significantly different to control group. By contrast Je-Cx43 did not have significantly difference between induction group and control group. However fish had various response to SPE induction, in accordance with a dividing point, GSI 1.5%, Je-Cx34.4 was significantly higher in GSI > 1.5% group (p<0.05); Je-Cx43 had a tendency to increase in GSI > 1.5% group, but without statistically significant difference. Our findings suggest that in the early stage of eel ovary, Je-Cx34.4 is an ovary specific Cx and may correlated with folliculogenesis; Je-Cx43 mRNA expression did not change but still had it appearance in early stage of oogenesis.
Subjects
Japanese eel
connexin
ovarian follicle
SPE Induction
oogenesis
GSI.
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-104-R02b45001-1.pdf
Size
23.32 KB
Format
Adobe PDF
Checksum
(MD5):09cc493f11012462551329b69a17668d