Cloning and bioinformatic analysis of full-length cDNA sequence of PsPII in tree peony (Paeonia suffruticosa)

In this study, using RACE-PCR method, the full-length cDNA of PsPII gene from cold-stress Lu Hehong buds was obtained and sequenced. The amplified fragment length of 5´RACE-PCR was 439bp and the full-length cDNA was 899bp, containing an open reading frame of 603bp, which encoded a 200 amino acid polypeptide. PII protein of tree peony was non-secretory and hydrophilic, and no had transmembrane domain. Its main secondary structure element was alpha helix. The prediction of subcellular localization showed that PsPII gene was located in the cytoplasm. Using the methods of bioinformatics, predictions of functional domains revealed that the expression of PII was linked to the level of nitrogen in the cell and PII protein was capable of sensing the level of C/N. By BLASTN, nitrogen regulatory protein PII modulated the activity of glutamine synthetase.