The protein of Myc modulator 1 (Mm-1) has been reported to repress the transcriptional activity of the proto-oncogene c-Myc in humans. Moreover, it was shown to be the subunit 5 of human prefoldin (PFD). So far, this gene and its homologs have been isolated and sequenced in many organisms, such as mammals and fish, but has not been sequenced for any amphibian or reptile. In order to better understand the function and evolution of Mm-1, we isolated a full-length Mm-1 cDNA (BgMm-1, GenBank accession no. EF211947) from Bufo gargarizans (Cantor, 1842) using RACE (rapid amplification of cDNA ends) methods. Mm-1 in B. gargarizans is 755 bp long, comprising an open reading frame (ORF) of 459 bp encoding 152 amino acids. The amino acid sequence had a prefoldin α-like domain, partially including a typical putative leucine zipper motif. BgMm-1 showed high similarity to its homolog of Mus musculus Linnaeus, 1758 (82%) and Homo sapiens Linnaeus, 1758 MM-1 isoform a (81%) at the amino acid level. The protein secondary structure modeled with the SWISS MODEL server revealed that there were two α-helices and four b-strands in BgMm-1 as its human orthologue, and both proteins belonged to the a class of PFD family. The phylogenetic relationships of Mm-1s from lower archaea to high mammals was consistent with the evolution of species, meanwhile the cluster result was consistent with the multiple alignment and the sequence identity analysis. RT-PCR (reverse transcriptase-polymerase chain reaction) analysis demonstrated that BgMm-1 expressed widely in ten tissues of adult toad. These results can be helpful for the further investigation on the evolution of Mm-1.

Sox (SRY-related HMG-box) genes encode a family of transcriptional regulators, which are characterized by a conserved 79-amino acid domain known as HMG-box. They play essential roles in a diverse range of processes including sex determination and the development of the central nervous system (CNS), neural crest and endoderm. In this paper, the HMG domain of ten distinct Sox gene family members (os-Sox2, os-Sox3a, os-Sox3b, os-Sox4, os-Sox11a, os-Sox11b, os-Sox14a, os-Sox14b, os-Sox21a, os-Sox21b) were isolated from both male and female Odorrana schmackeri (Boettger, 1892) using PCR, and no sexual differences were found. Molecular phylogenetic analysis of the HMG domain suggested that these ten Sox genes are members of the SoxB and SoxC groups. In addition, sequence analysis suggested that four Sox genes (os-Sox3, os-Sox11, os-Sox14, os-Sox21) were duplicated. The duplication-degeneration-complementation model should be implied to explain the evolution and diversity of the Sox gene family in O. schmackeri.