Plastocyanin controls the stabilization of the thylakoid Cu-transporting P-type ATPase PAA2/HMA8 in response to low copper in Arabidopsis.

ABSTRACT: PAA2/HMA8 (P-type ATPase of Arabidopsis/Heavy-metal-associated 8) is a thylakoid located copper (Cu)-transporter in Arabidopsis thaliana. In tandem with PAA1/HMA6, which is located in the inner chloroplast envelope, it supplies Cu to plastocyanin (PC), an essential cuproenzyme of the photosynthetic machinery. We investigated whether the chloroplast Cu transporters are affected by Cu addition to the growth media. Immunoblots showed that PAA2 protein abundance decreased significantly and specifically when Cu in the media was increased, while PAA1 remained unaffected. The function of SPL7, the transcriptional regulator of Cu homeostasis, was not required for this regulation of PAA2 protein abundance and Cu addition did not affect PAA2 transcript levels, as determined by qRT-PCR. We used the t

SUBMITTER: Tapken W 

PROVIDER: S-EPMC3365703 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature