Expression and localization of aquaporin 1b during oocyte development in the Japanese eel (Anguilla japonica)

Reproductive Biology and Endocrinology

Research

Hirohiko Kagawa¹  Takafumi Kishi¹  Hajime Matsubara²  Sayumi Sawaguchi³  Koichiro Gen⁴  Ryota Tosaka⁴  Yukinori Kazeto⁴  Takahiro Matsubara⁵ 

[1] Faculty of Agriculture, University of Miyazaki, 889-2192, Miyazaki, Japan;Faculty of Bioindustry, Tokyo University of Agriculture, 099-2493, Hokkaido, Japan;Hokkaido National Fisheries Research Institute, Fisheries Research Agency, 085-0802, Hokkaido, Japan;National Research Institute of Aquaculture, Fisheries Research Agency, 519-0423, Mie, Japan;South Ehime Fisheries Research Center, Ehime University, 798-4292, Ehime, Japan;

关键词: Oocyte Maturation;    Gilthead Seabream;    Yolk Mass;    Yolk Globule;    Oocyte Hydration;   

DOI  :  10.1186/1477-7827-9-71

 received in 2011-03-23, accepted in 2011-05-27,  发布年份 2011

来源: Springer

【 摘 要 】

To elucidate the molecular mechanisms underling hydration during oocyte maturation, we characterized the structure of Japanese eel (Anguilla japonica) novel-water selective aquaporin 1 (AQP1b) that thought to be involved in oocyte hydration. The aqp1b cDNA encodes a 263 amino acid protein that includes the six potential transmembrane domains and two Asn-Pro-Ala motifs. Reverse transcription-polymerase chain reaction showed transcription of Japanese eel aqp1b in ovary and testis but not in the other tissues. In situ hybridization studies with the eel aqp1b cRNA probe revealed intense eel aqp1b signal in the oocytes at the perinucleolus stage and the signals became faint during the process of oocyte development. Light microscopic immunocytochemical analysis of ovary revealed that the Japanese eel AQP1b was expressed in the cytoplasm around the yolk globules which were located in the peripheral region of oocytes during the primary yolk globule stage; thereafter, the immunoreactivity was observed throughout the cytoplasm of oocyte as vitellogenesis progressed. The immunoreactivity became localized around the large membrane-limited yolk masses which were formed by the fusion of yolk globules during the oocyte maturation phase. These results together indicate that AQP1b, which is synthesized in the oocyte during the process of oocyte growth, is essential for mediating water uptake into eel oocytes.

【 授权许可】

CC BY   
© Kagawa et al; licensee BioMed Central Ltd. 2011