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The apelin receptor (AR or APJ) is a class A (rhodopsin-like) G-protein-coupled receptor with wide distribution throughout the human body. Activation of the AR by its cognate peptide ligand, apelin, induces diverse physiological effects including vasoconstriction and dilation, strengthening of heart muscle contractility, angiogenesis, and regulation of energy metabolism and fluid homeostasis. Recently, another endogenous peptidic activator of the AR, Toddler/ELABELA, was identified as having a crucial role in zebrafish (Danio rerio) embryonic development. The AR is also implicated in pathologies including cardiovascular disease, diabetes, obesity, and cancer, making it a promising therapeutic target. Despite its established importance, the precise roles of AR signalling remain poorly understood. Moreover, little is known about the mechanisms of peptide-AR activation. Additional complexity arises from modulation of the AR by 2 endogenous peptide ligands, both with multiple bioactive isoforms of variable length and distribution. The various apelin and Toddler/ELABELA isoforms may also produce distinct cellular effects. Further complexity arises through formation of functionally distinct heterodimers between the AR and other G-protein-coupled receptors. This minireview outlines key (patho)physiological actions of the AR, addresses what is known about signal transduction downstream of AR activation, and concludes by discussing unique properties of the endogenous peptidic ligands of the AR. Key words: apelinergic system, APJ, APLNR, signal transduction, peptide-activated GPCR. Le recepteur de l'apeline (RA ou APJ) est un recepteur couple aux proteines G (RCPG) de classe A (de type rhodopsine), distribue largement dans tout le corps humain. L'activation du RA par son ligand peptidique apparente, l'apeline, induit divers effets physiologiques, notamment la vasoconstriction et la vasodilatation, le renforcement de la contractilite du muscle cardiaque, l'angiogenese et la regulation du metabolisme energetique et de l'homeostasie des liquides. Recemment, un autre activateur peptidique endogene du RA a ete identifie, Toddler/ELABELA, qui exerce un role crucial dans le developpement embryonnaire du poisson-zebre (Danio rerio). Le RA est aussi implique dans des pathologies incluant les maladies cardiovasculaires, le diabete, l'obesite et le cancer, ce qui en fait une cible therapeutique prometteuse. Malgre son importance etablie, le role precis de la signalisation par le RA demeure peu compris. De plus, les mecanismes de l'activation peptide-RA sont peu connus. Une complexite additionnelle emane de la modulation du RA par 2 peptides endogenes, possedant tous deux de multiples isoformes bioactives de longueurs et de distributions variables. Les differentes isoformes de l'apeline et de Toddler/ELABELA peuvent aussi produire des effets cellulaires distincts. Une complexite encore plus grande provient de la formation d'heterodimeres fonctionnellement distincts entre le RA et d'autres RCPG. Cette mini-revue souligne les actions (patho)physiologiques cles du RA, s'interesse a ce qui est connu des signaux de transduction agissant en aval de l'activation du RA, et se conclut en discutant des proprietes uniques des ligands peptidiques endogenes du RA. [Traduit par la Redaction] Mots-cles: systeme apelinergique, APJ, APLNR, transduction de signal, RCPG active par un peptide., Overview of the apelinergic system The apelin receptor (AR) is a class A (rhodopsin-like) G-protein-coupled receptor (GPCR) first identified in 1993 based on its sequence homology with the angiotensin II [...]

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The current status of civil registration and vital statistics (CRVS) systems in Asia and the Pacific is described in this paper, and the case is made for investing in CRVS. In addition, there is a summary of the development of the Regional Strategic Plan for the Improvement of Civil Registration and Vital Statistics in Asia and the Pacific. The paper highlights the fact that, while many countries in the ESCAP region do not have well-functioning CRVS systems, a new momentum for improving CRVS is building. This impetus is being driven by the growing demands for accountability and results and for improved equity and rights-based approaches to development challenges, and by the immense potential for innovation and new technologies to accelerate progress in CRVS improvement. The momentum is further reinforced by the Regional Strategic Plan, which has been endorsed by countries in the ESCAP region to stimulate and support the actions required to strengthen CRVS. [ABSTRACT FROM AUTHOR]