Cloning and Sequence Analysis of Mitogen-activated Protein Kinase Kinase Kinase Homolog from Volvariella volvacea(VV-MAPKKK)

Two pairs of degenerate primers were designed according to the conserved amino acid sequences of several mitogen-activated protein kinase kinase kinases(MAPKKK) from basidiomycetes.Based on the conserved DNA sequence,which was obtained by nested degenerate PCR,a whole DNA sequence of MAPKKK of Volvariella volvacea(VV-MAPKKK) was obtained by blasting with Volvariella volvacea genome.VV-MAPKKK gene,containing 4 introns and codeing for a 1405 aa protein(VV-MAPKKK),is 4434 bp in length.The similarity of VV-MAPKKK compared with Hog-MAPKKK protein from Cryptococcus neoformans,Paracoccidioides brasiliensis and Cochliobolus heterostrophus is 58%,57% and 56%,respectively.Phylogenetic analysis showed that VV-MAPKKK and Hog-MAPKKK protein homolog belong to the same clade.These data supported that VV-MAPKKK protein is a Hog-MAPKKK protein homolog from Volvariella volvacea.