Isolation and mRNA expression analysis of aquaporin isoforms in marine medaka Oryzias dancena, a euryhaline teleost.
We have identified six putative aquaporin (AQP) genes from marine medaka Oryzias dancena (named odAQPs 1, 3, 8, 10, 11 and 12). The marine medaka AQP cDNAs encode polypeptides of 259-298 amino acids, respectively. Topology predictions showed six transmembrane domains, five connecting loops, and cytoplasmic N- and C-terminal domains, all of which is conserved among AQP molecules. Although asparagine-proline-alanine (NPA) motifs are highly conserved in most odAQP isoforms, several AQPs revealed variant types of motifs such as asparagine-proline-proline (NPP), asparagine-proline-valine (NPV) or/and asparagine-proline-serine (NPS) motifs. The phylogenic analysis showed that marine medaka AQPs had closet relationship with Japanese ricefish (medaka; Oryzias latipes) counterparts. Reverse transcription (RT)-PCR analyses showed that marine medaka AQP transcripts would be expressed in not only osmoregulatory tissues but also nonosmoregulatory tissues, and also that the expression levels of certain AQP isoforms in nonosmoregulatory tissues were readily comparable or even higher than those in typically known osmoregulatory organs. Although the overall tissue distribution patterns of AQPs were not significantly different between 0- and 30-ppt acclimated fish, the expression levels under different salinities were largely variable among isoforms and tissues. This is the first report to investigate tissue expression profiles of teleostean AQPs 11 and 12 during the long-term acclimation to freshwater and salted water.
Department of Marine Bio-Materials and Aquaculture, Pukyong National University, Republic of Korea.
Yi Kyung
YK
Kim
Department of Marine Bio-Materials and Aquaculture, Pukyong National University, Republic of Korea.
Sang Yoon
SY
Lee
Department of Marine Bio-Materials and Aquaculture, Pukyong National University, Republic of Korea.
Byoung Soo
BS
Kim
Department of Marine Bio-Materials and Aquaculture, Pukyong National University, Republic of Korea.
Dong Soo
DS
Kim
Department of Marine Bio-Materials and Aquaculture, Pukyong National University, Republic of Korea. Electronic address: yoonknam@pknu.ac.kr.
Yoon Kwon
YK
Nam
D000595:Amino Acid Sequence; D000818:Animals; D020346:Aquaporins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics; D005091:Exons / Q000235:genetics; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D007438:Introns / Q000235:genetics; D008969:Molecular Sequence Data; D009928:Organ Specificity / Q000235:genetics; D009990:Oryzias / Q000235:genetics*; D010802:Phylogeny; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D054712:Salinity; D016415:Sequence Alignment
D020346:Aquaporins; D018076:DNA, Complementary; D020033:Protein Isoforms; D012333:RNA, Messenger
Aquaporin isoforms; Gene expression; Marine medaka Oryzias dancena