[Cloning and expression of Ser/Thr protein phosphatase type 5 during microcycle conidiation in Metarhizium ansopliae].

OBJECTIVE

To clone Ser/Thr protein phosphatase type 5 gene (PP5) from Metarhizium anisopliae, analyze the structure of PP5 gene with its encoding protein and expression profile during two conidiation program (microcycle conidiation and normal conidiation).

METHODS

The DNA sequence of PP5 was isolated by blasting the expressed sequence tags (EST) of PP5 in subtracted library with genomic data of M. anisopliae. Primers were designed based on the DNA sequence to clone the full length cDNA of PP5 by PCR, and the characteristics of the encoded protein was analyzed by online tools and biological softwares. The PP5 expression profile was quantified by real time PCR at different stages of microcycle conidiation and hyphal stage of normal conidiation in M. anisopliae.

RESULTS

The genomic DNA, which was interrupted by six introns, was 2100 bp long. The cDNA, encoding 325 amino acid residues, is 1428 bp. Analysis to Ser/ Thr protein phosphatase type 5 in M. anisopliae show a conserved structure features. Quantitative real time PCR analysis showed that PP5 expression varied obviously in different stages of microcycle conidiation. Expression was sharply up-regulated after 16 h, with the highest transcript levels at 24 h in microcycle conidiation, but lowly expressed in normal conidiation.

CONCLUSION

This work presents the first report about the detailed sequence and structure of PP5 from entomopathogenic fungi. Comparison of expression profile of microcycle conidiation and normal conidiation reveals that PP5 is principally involved in microcycle conidiation in M. anisopliae, and it provides ideal candidate for further studies to PP5 and its molecular regulation.