The admiR-able advances in cardiovascular biology through the zebrafish model system

Abstract

MicroRNAs are small non-coding RNAs endogenously expressed by all tissues during development and adulthood. They regulate gene expression by controlling the stability of targeted messenger RNA. In cardiovascular tissues microRNAs play a role by modulating essential genes involved in heart and blood vessel development and homeostasis. The zebrafish (Danio rerio) system is a recognized vertebrate model system useful to study cardiovascular biology; recently, it has been used to investigate microRNA functions during natural and pathological states. In this review, we will illustrate the advantages of the zebrafish model in the study of microRNAs in heart and vascular cells, providing an update on recent discoveries using the zebrafish to identify new microRNAs and their targeted genes in cardiovascular tissues. Lastly, we will provide evidence that the zebrafish is an optimal model system to undercover new microRNA functions in vertebrates and to improve microRNA-based therapeutic approaches.Keywords MicroRNA Á Zebrafish Á Heart Á Blood vessel Á Development MiRNAs: function and mechanismMicroRNAs (e.g., miRs or miRNAs) are evolutionary conserved small non-coding RNAs, usually 21-25 nt long, that regulate gene expression at a post-transcriptional level.

ZebraBeat: a flexible platform for the analysis of the cardiac rate in zebrafish embryos

“…The optical clarity of zebrafish embryos and larvae throughout embryogenesis allows the real time, in vivo observation of physiological or pathological events that occur during organ development. In this regard, the zebrafish is an optimal vertebrate model system for studying cardiovascular development and homeostasis 5 6 . In fact, the zebrafish has a relatively simple cardiac and vascular system, and the molecular mechanisms underlying vessel formation and morphogenesis are very similar to those of higher vertebrates, showing a remarkable degree of anatomical and functional conservation 7 .…”

Cardiac contraction and relaxation are regulated by beta 1 adrenergic receptor-generated cAMP pools at distinct membrane locations

“…The molecular mechanisms underlying their heart function are very similar to those of higher vertebrates 47 . The optical clarity of zebrafish embryos allows the real-time and in vivo visualization of the heart contractility responses and makes it a useful vertebrate model system for studying cardiovascular performance using optogenetic tools 48,49 . To measure cardiac outputs such as chronotropy, inotropy, and lusitropy, we generated transgenic zebrafish that express Golgi-bPAC (Extended Data Fig.…”

Tumor Angiogenesis: Fishing for Screening Models

“…Although it is known that several miRNAs are involved in angiogenesis (proand anti-angiogenesis) it mostly remain undetermined their vascular cell autonomous target [48]. Identification of miRNAs signature of different pathological vascular disorders such as tumor-induced angiogenesis could help to develop innovative anti-angiogenic cancer therapies.…”

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