Biology subjects

McCrea, P. D.

Publications and source records attributed to McCrea, P. D..

4 recordsLinked to original sources

bioRxiv2023

Sprr1 and miR-130b contribute to the senescence-like phenotype in aging

Aging is an inevitable process with senescence being one of its hallmarks. Recent advances have indicated that the elimination of senescent cells can reduce the signs of aging and increase healthy life span. Here, we identify a negative modulator of aging, Sprr1a, and in turn a negative modulator of Sprr1a, miR-130b. We show that reductions in Sprr1a levels, including via miR-130b expression, promotes cell senescence-like phenotype. We find that mediators of senescence, such as inflammatory cytokines and cell cycle regulators, are modulated by the miR-130b and Sprr1a-related pathway. For example, the levels of p16, p53 and p21 become decreased or increased upon the respective expression of Sprr1a versus miR-130b. Further, as shown in relation to p16 levels and {beta}-galactosidase levels, cells expressing Sprr1a exhibit significant protection from senescence-inducing factors such as radiation or Doxorubicin, suggesting that Sprr1a might contribute to protection against age-related pathologies. Taken together, we introduce two modulators of properties associated with senescence-like phenotype.

molecular biology↗

bioRxiv2023

Role of a Pdlim5:PalmD complex in directing dendrite morphology

Neuronal connectivity is regulated during normal brain development with the arrangement of spines and synapses being dependent on the morphology of dendrites. Further, in multiple neurodevelopmental and aging disorders, disruptions of dendrite formation or shaping is associated with atypical neuronal connectivity. We showed previously that Pdlim5 binds delta-catenin and promotes dendrite branching (Baumert et al., J Cell Biol 2020). We report here that Pdlim5 interacts with PalmD, a protein previously suggested by others to interact with the cytoskeleton (e.g., via adducin/spectrin) and to regulate membrane shaping. Functionally, the knockdown of PalmD or Pdlim5 in rat primary hippocampal neurons dramatically reduces branching and conversely, PalmD exogenous expression promotes dendrite branching as does Pdlim5. Further, we show that each proteins effects are dependent on the presence of the other. In summary, using primary rat hippocampal neurons we reveal the contributions of a novel Pdlim5:PalmD protein complex, composed of functionally inter-dependent components responsible for shaping neuronal dendrites.

neuroscience↗

bioRxiv2022

Epigenetic and Signaling Determinants of Blood-Brain Barrier-Regulatory Genetic Networks

The blood-brain barrier (BBB) controls the movement of molecules into and out of the central nervous system (CNS). Since a functional BBB forms by mouse embryonic day E15.5, we reasoned that gene cohorts expressed in CNS endothelial cells (EC) at E13.5 contribute to BBB formation. In contrast, adult gene signatures reflect BBB maintenance mechanisms. Supporting this hypothesis, transcriptomic analysis revealed distinct cohorts of EC genes involved in BBB formation and maintenance. Here, we demonstrate that epigenetic regulators histone deacetylase 2 (HDAC2) and polycomb repressive complex 2 (PRC2) control EC gene expression for BBB development and prevent Wnt/{beta}-catenin (Wnt) target genes from being expressed in adult CNS ECs. Low Wnt activity during development modifies BBB genes epigenetically for the formation of functional BBB. As a Class-I HDAC inhibitor induces adult CNS ECs to regain Wnt activity and BBB genetic signatures that support BBB formation, our results inform strategies to promote BBB repair.

neuroscience↗

bioRxiv2019

The Role of the Wnt/PCP Formin Daam1 in Renal Ciliogenesis

Kidneys are composed of numerous ciliated epithelial tubules called nephrons. Each nephron functions to reabsorb nutrients and concentrate waste products into urine. Defects in primary cilia are associated with abnormal formation of nephrons and cyst formation in a wide range of kidney disorders. Previous work in Xenopus laevis and zebrafish embryos established that loss of components that make up the Wnt/PCP pathway, Daam1 and ArhGEF19 (wGEF) perturb kidney tubulogenesis. Dishevelled, which activates both the canonical and non-canonical Wnt/PCP pathway, affect cilia formation in multiciliated cells. In this study, we investigated the role of the noncanoncial Wnt/PCP components Daam1 and ArhGEF19 (wGEF) in renal ciliogenesis utilizing polarized mammalian kidney epithelia cells (MDCKII and IMCD3) and Xenopus laevis embryonic kidney. We demonstrate that knockdown of Daam1 and ArhGEF19 in MDCKII and IMCD3 cells leads to loss of cilia, and Daam1s effect on ciliogenesis is mediated by the formin-activity of Daam1. Moreover, Daam1 co-localizes with the ciliary transport protein IFT88. Interestingly, knocking down Daam1 in Xenopus kidney does not lead to loss of cilia. This data suggests a new role for Daam1 in the formation of primary cilia.

molecular biology↗