Cysteine-rich receptor-like kinases (CRKs) are transmembrane proteins characterized by the presence of two domains of unknown function 26 (DUF26) in their ectodomain. The CRKs form one of the largest groups of receptor-like protein kinases in plants, but their biological functions have so far remained largely uncharacterized. We conducted a large-scale phenotyping approach of a nearly complete crk T-DNA insertion line collection showing that CRKs control important aspects of plant development and stress adaptation in response to biotic and abiotic stimuli in a non-redundant fashion. In particular, the analysis of reactive oxygen species (ROS)-related stress responses, such as regulation of the stomatal aperture, suggests that CRKs participate in ROS/redox signalling and sensing. CRKs play general and fine-tuning roles in the regulation of stomatal closure induced by microbial and abiotic cues. Despite their great number and high similarity, large-scale phenotyping identified specific functions in diverse processes for many CRKs and indicated that CRK2 and CRK5 play predominant roles in growth regulation and stress adaptation, respectively. As a whole, the CRKs contribute to specificity in ROS signalling. Individual CRKs control distinct responses in an antagonistic fashion suggesting future potential for using CRKs in genetic approaches to improve plant performance and stress tolerance.

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Ccc2p is homologous to the human Menkes and

The renin-angiotensin system (RAS) has been known for more than a century as a cascade that regulates body fluid balance and blood pressure. Angiotensin Ⅱ (Ang Ⅱ) has many functions in different tissues; however it is on the kidney that this peptide exerts its main functions. New enzymes, alternative routes for Ang Ⅱ formation or even active Ang Ⅱ-derived peptides have now been described acting on Ang Ⅱ AT1 or AT2 receptors, or in receptors which have recently been cloned, such as Mas and AT4. Another interesting observation was that old members of the RAS, such as angiotensin converting enzyme (ACE), renin and prorenin, well known by its enzymatic activity, can also activate intracellular signaling pathways, acting as an outside-in signal transduction molecule or on the renin/(Pro)renin receptor. Moreover, the endocrine RAS, now is also known to have paracrine, autocrine and intracrine action on different tissues, expressing necessary components for local Ang Ⅱ formation. This in situ formation, especially in the kidney, increases Ang Ⅱ levels to regulate blood pressure and renal functions. These discoveries, such as the ACE2/Ang-(1-7)/Mas axis and its antangonistic effect rather than classical deleterious Ang Ⅱ effects, improves the development of new drugs for treating hypertension and cardiovascular diseases. Key words: Renin-angiotensin system; Angiotensin Ⅱ; Kidney; Hypertension treatment; Receptor Core tip: Activation of the angiotensin converting enzyme (ACE)/ Angiotensin Ⅱ (Ang Ⅱ)/AT1 axis leads to vasoconstriction, anti-diuresis, anti-natriuresis, release of aldosterone and anti-diuretic hormone, which can result in hypertension, renal and cardiovascular diseases. Inhibition of renin and ACE or blocking AT1 receptor is the most used therapies for heart failure and hypertension. Nevertheless, the discovery of local Ang Ⅱ synthesis, new Ang Ⅱ metabolites, receptors and axis of this system, makes possible the development of new drugs and strategies for renal and cardiovascular diseases treatment, such as activation of ACE2/Ang-(1-7)/ Mas axis, which presents opposite effects of AT1 activation by Ang Ⅱ.