Developmental regulation of epithelial polarization by pre-mRNA splicing

mRNA前体剪接对上皮极化的发育调节

基本信息

批准号：
10583675
负责人：
Michel Bagnat
金额：
$ 46.19万
依托单位：
DUKE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-02-01 至 2026-11-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10583675
关键词：
Affect Amino Acids Apical Automobile Driving Biological Cell Polarity Clathrin Adaptors Complex Data Defect Degradation Pathway Dependence Development Diarrhea Dietary Proteins Digestion Disease Endocytosis Endosomes Enterocytes Epithelial Cells Epithelium Food Gastrointestinal tract structure Genes Genetic Genetic Screening Goals Golgi Apparatus Homeostasis Impairment Intestinal Absorption Intestines Introns Ion Channel Lipids Lysosomes Malabsorption Syndromes Malignant Neoplasms Membrane Proteins Membrane Transport Proteins Minor Modeling Morphology Mucins Mutation NGFR Protein Nutrient Pathway interactions Physiological Physiology Play Polysaccharides Process Protein Glycosylation Protein Sortings Proteins Proton-Translocating ATPases RNA Splicing Regulation Role Sorting Surface System Systemic disease Testing Transcript Transmembrane Transport Vacuole Visual Zebrafish absorption apical membrane basolateral membrane fluorescence imaging forward genetics glycosylation improved in vivo intestinal epithelium intestinal maturation intrinsic factor-cobalamin receptor mRNA Precursor mutant nutrient absorption organ growth particle public health relevance receptor segregation sugar superresolution microscopy trafficking transcriptional coactivator p75 transcriptome sequencing uptake vacuolar H+-ATPase

项目摘要

Abstract The apical membrane of epithelial cells in the intestine play critical roles in physiology and homeostasis. Many specialized functions of intestinal epithelial cells, such as nutrient absorption, depend on faithfully sorting proteins to the apical membrane during biosynthetic delivery. However, the cellular mechanisms driving apical membrane protein sorting and how it matures during development are poorly defined. Also unknown is what controls the onset of apical endocytosis in Lysosome Rich Enterocytes (LREs). To discover mechanisms of apical membrane polarization in vivo, we performed a forward genetics screen for factors required for sorting of a model apical cargo (O-glycan-GFP, Og-GFP) in the zebrafish intestine. We isolated distinct classes of mutants affecting apical Og-GFP sorting. Our preliminary data has uncovered a pH-dependent mechanism for sorting membrane proteins in subapical endosomes either to the degradative pathway or to the apical membrane. We also discovered a role for regulated pre-mRNA intron splicing in activating apical membrane transport pathways crucial for polarized protein delivery in enterocytes and for apical endocytosis in LREs of the developing intestine. Our studies will uncover genetic and cellular mechanisms crucial for the maturation of a fully polarized and physiologically active epithelium in the vertebrate gut.

抽象的肠中上皮细胞的顶膜在生理和稳态中起关键作用。许多肠上皮细胞的专业功能，例如营养吸收，取决于忠实分类蛋白生物合成期间的顶膜。但是，驱动顶膜的细胞机制蛋白质排序及其在发育过程中的成熟方式的定义很差。也未知是什么控制富含溶酶体的肠肠细胞（LIRS）中顶端内吞作用的发作。发现顶膜的机制在体内极化，我们为分类模型顶端所需的因素进行了正向遗传学屏幕斑马鱼肠中的货物（O-Glycan-GFP，OG-GFP）。我们隔离了影响根尖的突变体的不同类别 OG-GFP排序。我们的初步数据发现了一种pH依赖性机制，用于分类膜蛋白在降解途径或根尖膜的亚尖内体中。我们还发现了一个角色对于受调节的前MRNA内含子剪接，激活顶膜传输途径对于极化至关重要肠肠细胞中的蛋白质递送和发育中的肠道中的根尖内吞作用。我们的研究将发现遗传和细胞机制对于完全极化和生理活性的成熟至关重要脊椎动物肠道上皮。