Gene structure and expression of metallothionein during metal exposures in Hemibarbus mylodon.
Metallothionein gene was characterized in Hemibarbus mylodon, an endangered fish species. H. mylodon MT shared a high homology with other vertebrate MTs, including (1) tripartite exon/intron structure, (2) typical regulatory elements such as MREs and GC boxes in the 5'-flanking region, and (3) high proportion of Cysteines (33.3%) in its amino acid sequence. MT mRNA was ubiquitously detected in various tissues. Basal level of MT mRNA was the highest in ovary while the lowest in heart. Transcription of MT was highly inducible by exposures to waterborne cadmium (0.1-10 microM), copper (2-10 microM) or zinc (2-10 microM), based on real-time RT-PCR. Cadmium was more potent for the stimulation of MT transcripts than copper and zinc. Liver was more responsive to heavy metals than kidney and gill. In overall, the transcriptional activation of MT gene by metal exposures followed a dose- and/or time-dependent fashion.
Cho
Young Sun
YS
Department of Aquaculture, Pukyong National University (PKNU), Busan 608-737, Republic of Korea.
Lee
Sang Yoon
SY
Kim
Keun-Yong
KY
Bang
In Chul
IC
Kim
Dong Soo
DS
Nam
Yoon Kwon
YK
D000375:Aging; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003247:Conservation of Natural Resources; D003531:Cypriniformes / Q000235:genetics* / Q000378:metabolism*; D018076:DNA, Complementary / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects* / Q000502:physiology; D005880:Gills / Q000378:metabolism; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008668:Metallothionein / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008670:Metals / Q000494:pharmacology*; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013997:Time Factors
D018076:DNA, Complementary; D008670:Metals; D012333:RNA, Messenger; D008668:Metallothionein