A Novel Metallothionein Gene from Mussel, Hyriopsis cumingii: Identification and Expression under Lanthanum Exposure

Abstract

Metallothionein (MT) is a superfamily of cysteine‐rich, metal‐binding, low‐molecular‐weight proteins that participate in the storage, transportation, and metabolism of the trace metal elements. In this study, a novel MT gene from Hyriopsis cumingii was cloned (designated HcMT1); it shared 59.2% identity with previously published MT sequence of H. cumingii and 56.1–97.3% identity with other MT genes from mollusks. The expression level of HcMT1 in various tissues was determined by real‐time polymerase chain reaction. Relatively higher expression levels were observed in digestive gonad, mantle, and gill, and the expression level in hemocytes was significantly upregulated by lanthanum (La3+) exposure. The nucleotide sequence of HcMT1 amplified from genomic DNA is identical to the cDNA template group under La3+ exposure, which indicated that HcMT1 is an intronless gene. These results indicate that HcMT1 may play an important role in La3+ metabolism.

Diversification and domain evolution of molluskan metallothioneins: a mini review

“…They represent 66-aa polypeptides containing 19 Cys residues with the deletion of one Cys-X-Cys motif in the α-domain. All the three MT sequences are originated from intronless MT genes (Leignel et al 2005;Yang et al 2014). The second group contains twenty-four MT10 isoform sequences.…”