title: Expression Patterns of CREBs in Oocyte Growth and Maturation of Fish.
abstract: In fish, oocyte meiotic maturation is regulated by 17α, 20β-dihydroxy-progesterone through cAMP. To study the role of cAMP response element binding protein (CREB) in meiotic maturation, we cloned and characterized the expression pattern of CREBs from two fish models, the Nile tilapia and catfish. In the Nile tilapia three different CREBs were identified where in CREB1 was found in many tissues including gonads with abundant expression in testis. CREB2, few amino acids shorter than CREB1, was expressed in several tissues with abundant expression in ovary. In addition, a 3'UTR variant form, CREB3 was exclusively found in ovary. During natural 14-day ovarian cycle of the Nile tilapia, CREB1 expression was stable throughout vitellogenesis with a sharp decrease on the day of spawning. In contrast, CREB2 remain unchanged throughout the ovarian cycle, however elevated in 11-day full-grown immature ovarian follicle and after hCG-induction. Interestingly, CREB3 expression was induced three folds on the day of spawning as well as during hCG-induced oocyte maturation. Based on the synergistic expression pattern, CREB1 is likely to control oocyte growth, whereas CREB 2 and 3 contribute to oocyte maturation in tilapia and the latter seems to be critical. In catfish, a single form of CREB showed a maximum expression during spawning phase and hCG-induced maturation both in vivo and in vitro augmented CREB expression. These results suggest that spatial and temporal expression of CREBs seems to be important for final oocyte maturation and may also regulate oocyte growth in fish.
authors.affiliation: Department of Animal Biology, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad, 500 046, Telangana, India.|Laboratory of Reproductive Biology, National Institute for Basic Biology, Myodaiji, Okazaki, 444-8585, Japan.
authors.forename: Balasubramanian
authors.initials: B
authors.lastname: Senthilkumaran
authors.affiliation: Department of Animal Biology, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad, 500 046, Telangana, India.
authors.forename: Gunti
authors.initials: G
authors.lastname: Sreenivasulu
authors.affiliation: Laboratory of Reproductive Biology, National Institute for Basic Biology, Myodaiji, Okazaki, 444-8585, Japan.
authors.forename: De-Shou
authors.initials: DS
authors.lastname: Wang
authors.affiliation: Department of Animal Biology, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad, 500 046, Telangana, India.|Laboratory of Reproductive Biology, National Institute for Basic Biology, Myodaiji, Okazaki, 444-8585, Japan.
authors.forename: Cheni-Chery
authors.initials: CC
authors.lastname: Sudhakumari
authors.affiliation: Laboratory of Reproductive Biology, National Institute for Basic Biology, Myodaiji, Okazaki, 444-8585, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Kobayashi
authors.affiliation: Laboratory of Reproductive Biology, National Institute for Basic Biology, Myodaiji, Okazaki, 444-8585, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Nagahama
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002397:Catfishes / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D017362:Cyclic AMP Response Element-Binding Protein / Q000235:genetics / Q000378:metabolism*; D018076:DNA, Complementary / Q000737:chemistry; D005260:Female; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism*; D020869:Gene Expression Profiling; D008297:Male; D008969:Molecular Sequence Data; D009865:Oocytes / Q000254:growth & development / Q000378:metabolism*; D010802:Phylogeny; D016415:Sequence Alignment; D017210:Tilapia / Q000235:genetics / Q000378:metabolism*; D014818:Vitellogenesis
chemical_list: D017362:Cyclic AMP Response Element-Binding Protein; D018076:DNA, Complementary; D029941:Fish Proteins