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Kraut, A.

Publications and source records attributed to Kraut, A..

2 recordsLinked to original sources

Molecular flux control encodes distinct cytoskeletal responses by specifying SRC signaling pathway usage.

Multi-domain signaling proteins sample numerous stimuli to coordinate distinct cellular responses. Understanding the mechanisms of their pleiotropic signaling activity requires to directly manipulate their activity of decision leading to distinct cellular responses. We developed an optogenetic probe, optoSRC, to control spatio-temporally the SRC kinase, a representative example of versatile signaling node, and challenge its ability to generate different cellular responses. Genesis of different local molecular fluxes of the same optoSRC to adhesion sites, was sufficient to trigger distinct and specific acto-adhesive responses. Collectively, this study reveals how hijacking the pleiotropy of SRC signaling by modulating in space and time subcellular molecular fluxes of active SRC kinases.

cell biology

Identification of the Calmodulin-dependent NAD+ kinase sustaining the elicitor-induced oxidative burst in plants

NADP(H) is an essential cofactor ofmultiple metabolic processes in all living organisms. While NADP+ production in plants has long been known to involve a Calmodulin (CaM)/Ca2+-dependent NAD+ kinase, the nature of the enzyme catalyzing this activity has remained enigmatic, as well as its role in plant physiology. Here, we identify an Arabidopsis P-loop ATPase (Atlg04280) with a bacterial type II zeta toxin domain, that catalyzes NADP+ production upon binding of CaM/Ca2+ to a domain located in its N-terminal region. The encoded protein (NADKc-1) is associated with the mitochondria and amplifies the elicitor-induced oxidative burst in Arabidopsis leaves representing the missing link between calcium signalling and metabolism in the response to pathogen elicitor. By analysis of various plants and algae, we show that NADKc is well conserved in the plant lineage and present in basal plants. Our data allows proposing that the CaM-dependent NAD kinase activity is only found in photosynthetic species carrying NADKc-1 related proteins, which would represent the only proteins harboring CaM-dependent NAD kinase activity in plants and algae.

plant biology