Cysteine-rich protein 2 accelerates actin filament cluster formation

Crip2 affects vascular development by fine-tuning endothelial cell aggregation and proliferation

Endothelial cell adhesion and migration are crucial to various biological processes, including vascular development. The identification of factors that modulate vascular development through these cell functions has emerged as a prominent focus in cardiovascular research. Crip2 is known to play a crucial role in cardiac development, yet its involvement in vascular development and the underlying mechanism remains elusive. In this study, we revealed that Crip2 is expressed predominantly in the vascular system, particularly in the posterior cardinal vein and caudal vein plexus intersegmental vein. Upon Crip2 loss, the posterior cardinal vein plexus and caudal vein plexus are hypoplastic, and endothelial cells exhibit aberrant aggregation. In human umbilical vein endothelial cells (HUVECs), CRIP2 interacts with the cytoskeleton proteins KRT8 and VIM. The absence of CRIP2 negatively regulates their expression, thereby fine-tuning cytoskeleton formation, resulting in a hyperadhesive phenotype. Moreover, CRIP2 deficiency perturbs the VEGFA/CDC42 signaling pathway, which in turn diminishes the migrating capacity of HUVECs. Furthermore, the loss of CRIP2 impairs cell proliferation by affecting its interaction with SRF through PDE10A/cAMP and PDGF/JAK/STAT/SRF signaling. Collectively, our findings delineate a crucial role for CRIP2 in controlling the migration, adhesion and proliferation of endothelial cells, thereby contributing to vascular development in zebrafish. These insights may provide a deeper understanding of the etiology of cardiovascular disorders.

Insights on the Pathogenesis of Aneurysm through the Study of Hereditary Aortopathies

Thoracic aortic aneurysms (TAA) are permanent and localized dilations of the aorta that predispose patients to a life-threatening risk of aortic dissection or rupture. The identification of pathogenic variants that cause hereditary forms of TAA has delineated fundamental molecular processes required to maintain aortic homeostasis. Vascular smooth muscle cells (VSMCs) elaborate and remodel the extracellular matrix (ECM) in response to mechanical and biochemical cues from their environment. Causal variants for hereditary forms of aneurysm compromise the function of gene products involved in the transmission or interpretation of these signals, initiating processes that eventually lead to degeneration and mechanical failure of the vessel. These include mutations that interfere with transduction of stimuli from the matrix to the actin-myosin cytoskeleton through integrins, and those that impair signaling pathways activated by transforming growth factor-β (TGF-β). In this review, we summarize the features of the healthy aortic wall, the major pathways involved in the modulation of VSMC phenotypes, and the basic molecular functions impaired by TAA-associated mutations. We also discuss how the heterogeneity and balance of adaptive and maladaptive responses to the initial genetic insult might contribute to disease.