PRDA1 is a chloroplast nucleoid protein that is involved in the regulation of plastid gene expression and is required for early chloroplast development. It may positively regulate plastid-encoded RNA polymerase (PEP) activity through its interaction with two other proteins known to be essential for PEP-related chloroplast development, MRL7 and FSD2 [].
This entry includes proteins RESPONSE TO LOW SULFUR 1-4 (LSU1-4) from Arabidopsis. These proteins may be involved in plant responses to environmental challenges; they are up-regulated in several abiotic and biotic stress conditions []. Three out of four of the Arabidopsis LSU genes (namely LSU1, LSU2, and LSU3) are induced by sulfur deficiency []. LSU expression prevents chloroplastic reactive oxygen species (ROS) production and proper stomatal closure during sulphur stress. LSU1 has been shown to interact with and stimulates the activity of the chloroplastic superoxide dismutase FSD2 []. Homologues are known only from plants.
