Sex-specific regulation of AMP-activated protein kinase (AMPK) in the Pacific oyster Crassostrea gigas.
The hermaphrodite Pacific oyster Crassostrea gigas displays a high energy allocation to reproduction. We studied the expression of AMP-activated protein kinase (AMPK) during gametogenesis in the gonad and characterized the mRNA sequences of the AMPK subunits: the AMPK alpha mRNA sequence was previously characterized; we identified AMPK beta, AMPK gamma, and mRNAs of putative AMPK-related targets following bioinformatics mining on existing genomic resources. We analyzed the mRNA expression of the AMPK alpha, beta, and gamma subunits in the gonads of male and female oysters through a reproductive cycle, and we quantified the mRNA expression of genes belonging to fatty acid and glucose metabolism. AMPK alpha mRNA levels were more abundant in males at the first stage of gametogenesis, when mitotic activity and the differentiation of germinal cells occur, and were always more abundant in males than in females. Some targets of fatty acid and glucose metabolism appeared to be correlated with the expression of AMPK subunits at the mRNA level. We then analyzed the sex-specific AMPK activity by measuring the phosphorylation of the catalytic AMPK alpha protein and its expression at the protein level. Both the amount of AMPK alpha protein and threonine 172 phosphorylation appeared to be almost totally inhibited in mature female gonads at stage 3, at the time when accumulation of reserves in oocytes was promoted, while it remained at a high level in mature spermatozoa. Its activation might play a sex-dependent role in the management of energy during gametogenesis in oyster.
Ifremer, Laboratoire des Sciences de l'Environnement Marin (UMR 6539, LEMAR), Plouzané, France.
Eric
E
Guévélou
Arnaud
A
Huvet
Clara E
CE
Galindo-Sánchez
Massimo
M
Milan
Virgile
V
Quillien
Jean-Yves
JY
Daniel
Claudie
C
Quéré
Pierre
P
Boudry
Charlotte
C
Corporeau
D055372:AMP-Activated Protein Kinases / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D017756:Aquaculture; D019295:Computational Biology; D049896:Crassostrea / Q000502:physiology*; D057225:Data Mining; D004734:Energy Metabolism; D004789:Enzyme Activation; D005260:Female; D005602:France; D005718:Gametogenesis; D018507:Gene Expression Regulation, Developmental; D006066:Gonads / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D008297:Male; D010766:Phosphorylation; D010802:Phylogeny; D011499:Protein Processing, Post-Translational; D021122:Protein Subunits / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D012727:Sex Characteristics; D013912:Threonine / Q000378:metabolism
D021122:Protein Subunits; D012333:RNA, Messenger; D013912:Threonine; D055372:AMP-Activated Protein Kinases
AMP-activated protein kinase; Crassostrea gigas; gametogenesis; marine bivalve; reproduction