Polyamine sensitivity of gap junctions is required for skin pattern formation in zebrafish.
Gap junctions allow the direct and bidirectional transfer of small molecules between cells. Polyamine sensitivity, which has been observed for a certain gap junction in vitro, confers rectification property to gap junction. Here we report that the polyamine sensitivity of gap junctions in vivo is crucial for skin pattern formation in zebrafish. Transgenic experiments have revealed that several connexin genes were able to rescue the spot phenotype of mutant zebrafish. Mutational analyses of the N-terminal region of connexins revealed that the ExxxE motif, a hypothetical polyamine-binding site, was important for connexin's role in pattern formation. Ectopic expression of spermidine/spermine N(1)-acetyltransferase (SSAT), a polyamine metabolic enzyme, also caused stripe pattern changes, which further indicates that the polyamine sensitivity of gap junctions is crucial. This is the first report to show that polyamine sensitivity has a physiologically relevant function and is related to skin pattern formation in animals.
Graduate School of Frontier Biosciences, Osaka University 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan. watanabe-m@fbs.osaka-u.ac.jp
Masakatsu
M
Watanabe
Daisuke
D
Watanabe
Shigeru
S
Kondo
D000123:Acetyltransferases / Q000235:genetics; D020816:Amino Acid Motifs / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D001665:Binding Sites / Q000235:genetics; D019521:Body Patterning / Q000235:genetics; D017630:Connexins / Q000145:classification / Q000235:genetics; D017629:Gap Junctions / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D011073:Polyamines / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D012867:Skin / Q000254:growth & development / Q000378:metabolism*; D015027:Zebrafish / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000235:genetics; D000099228:Diamine N-Acetyltransferase
D000123:Acetyltransferases; D017630:Connexins; D011073:Polyamines; D029961:Zebrafish Proteins; D000099228:Diamine N-Acetyltransferase