Cloning And Expression Analyse Of A Penicillium Janthinillum GXCR Copper Transporting P-Type Atpase Gene

Copper ion homeostasis is complicated in that copper is an essential elementneeded for a variety of cellular processes but is toxic at excess levels. Cells haveevolved mechanisms to provide intracellular copper ion homeostasis. The keyenzyme involved in this balance mechanisms is copper-transporting P-typeATPase. The cDNA of copper transporting P-type ATPase of Penicilliumjanthinillum, named GXCR, wascloned by 3'RACE, PCR and silicon cloning. Itharbored a 3720bp open reading frame(ORF), encoded a putative protein of 1240amino acids. Its molecular weight was approximately 132KD. The cDNA ofGXCR showed 93% identity with the copper transporting ATPase of Aspergillusclavatus NRRL 1. SMART analyses revealed that the encoding product have 7transmembrane domains.It have several domains conserved in all P-type ATPase.CPX motif which is the defining element of P_1B-type ATPase and conserved HPlocus were also found, real-time fluorescence quantitative PCR (Q-PCR) andNorthern blot analyses revealed that, expression level of copper transportingP-type ATPase was significantly induced by 40mM Cu²⁺stress, the highestexpression was detected at time of 30 min, expression was declined after 1hour.The transcription of the gene also increase when the cell was induced byAg⁺ and Cd²⁺.