WD 40 domain of RqkA regulates its kinase activity and role in extraordinary radioresistance in Deinococcus radiodurans

BioRxiv : the Preprint Server for Biology
D. K. SharmaYogendra S Rajpurohit


RqkA, a DNA damage responsive Serine / Threonine kinase DNA repair and cell division in D. radiodurans. It has a unique combination of a kinase domain at N-terminus and a WD40 type domain at C-terminus joined through a linker. WD40 domain is comprised of eight {beta} propeller repeats held together via 'tryptophan-docking motifs' and forming a typical 'velcro' closure structure. The RqkA mutants lacking the WD40 region (hereafter referred to as WD mutant) could not complement RqkA loss in {gamma} radiation resistance in D. radiodurans and lacked {gamma} radiation mediated activation of kinase activity in vivo. WD mutants failed to phosphorylate its cognate substrate (e.g. DrRecA) in surrogate E. coli cells. Further, unlike wild type enzyme, the kinase activity of its WD40 mutants was not stimulated by Pyrroloquinoline quinine (PQQ) indicating the role of the WD motifs in PQQ interaction and stimulation of its kinase activity. Together, results highlighted the importance of the WD40 domain in the regulation of RqkA kinase signaling functions in vivo and thus the role of the WD40 domain in the regulation of any STPK is the first time demonstrated in bacteria.

Related Concepts

TP53 gene
Biochemical Pathway
Receptors, Notch
Human Papillomavirus
Gene Knockdown Techniques
Arachidonic Acid

Related Feeds

Carcinoma, Squamous Cell

Basal cell carcinoma is a form of malignant skin cancer found on the head and neck regions and has low rates of metastasis. Discover the latest research on basal cell carcinoma here.

BioRxiv & MedRxiv Preprints

BioRxiv and MedRxiv are the preprint servers for biology and health sciences respectively, operated by Cold Spring Harbor Laboratory. Here are the latest preprint articles (which are not peer-reviewed) from BioRxiv and MedRxiv.