Up-regulation of P450arom and down-regulation of Dmrt-1 genes in the temperature-dependent sex reversal from genetic males to phenotypic females in a salamander.
When larvae of the salamander Hynobius retardatus were reared at a high temperature (28 degrees C) during their thermosensitive period (TSP=15-30 days after hatching), all larvae developed to phenotypic females irrespective of their genetic sexes. Hynobius P450 aromatase (P450arom) and Dmrt-1 complementary DNAs were isolated and their expression patterns were analyzed by competitive and conventional reverse transcriptase-polymerase chain reaction. While the P450arom gene was expressed predominantly in the ovary, Dmrt-1 was expressed exclusively in the testis. When larvae were reared at the female-producing temperature (28 degrees C) during the TSP, a strong expression of the P450arom gene and a complete suppression of the Dmrt-1 gene were induced in all experimental larvae. Up-regulation of the P450arom gene and down-regulation of the Dmrt-1 gene even in genetic males constitute a part of the molecular biological cascade for the temperature-dependent sex reversal from genetic males to phenotypic females in this salamander.
Sakata
Natsuko
N
Division of Biological Sciences, Graduate School of Science, Hokkaido University, 060-0810 Sapporo, Japan.
Miyazaki
Kinuko
K
Wakahara
Masami
M
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D001141:Aromatase / Q000235:genetics*; D001831:Body Temperature / Q000235:genetics*; D018076:DNA, Complementary; D012734:Disorders of Sex Development; D015536:Down-Regulation; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D008297:Male; D008969:Molecular Sequence Data; D010053:Ovary / Q000201:enzymology; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D012733:Sex Differentiation / Q000235:genetics*; D013696:Temperature; D013737:Testis / Q000201:enzymology; D015854:Up-Regulation; D014562:Caudata / Q000235:genetics* / Q000254:growth & development
D018076:DNA, Complementary; D001141:Aromatase