Cloning And Analysis Of Promoter Elements Of A Ser/Thr Protein Kinase Gene Homologue From Piper Colubrinum Link

Serine/Threionine (Ser/Thr) protein kinases are multifarious phosphorylation enzymes which also play a central role in signalling events following pathogen recognition in plants. The present study describes cloning and characterisation of upstream promoter region of a Ser/Thr protein kinase (STPK) gene from Piper colubrinum (PcSTPK), a wild species highly resistant to fungal pathogens in the Piper germplasm. The gene was found to be pathogen responsive when challenged with oomycete pathogen - Phytophthora capsici. Transcript abundance of PcSTPK was determined by quantitative real timepolymerase chain reaction (qRT-PCR) which demonstrated maximum transcript accumulation of PcSTPK in inflorescence, followed by leaf, stem and root tissues. Inoculation of leaf tissues with the oomycete pathogen Phytophthora capsici, also induced significant transcript accumulation of PcSTPK in the plant. Genome walking methodology was adopted to clone upstream promoter elements of PcSTPK. In silico analysis revealed the presence of regulatory elements for light responsiveness, meristem and endosperm expression in addition to various hormone responsive elements. Our results suggest that PcSTPK along with its cis-regulatory elements has a role in modulation of plant stress response.