Role of Rab proteins in hSVCT1 cell biology in intestinal epithelial cells

Rab 蛋白在肠上皮细胞 hSVCT1 细胞生物学中的作用

• 批准号: 7701378
• 负责人: VEEDAMALI S SUBRAMANIAN
• 金额: $ 6.36万
• 依托单位: SOUTHERN CALIFORNIA INST FOR RES/EDUC
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7701378
• 关键词: Affect; Antibodies; Area; Ascorbic Acid; Ascorbic Acid Deficiency; Biochemical; Biological; Biological Models; Caco-2 Cells; Cardiovascular Diseases; Carrier Proteins; Cataract; Cell Fractionation; Cell membrane; Cell physiology; Cells; Cellular biology; Clinical; Confocal Microscopy; Connective Tissue; Cytomegalovirus Infections; Data; Diet; Docking; DsRed; Endosomes; Enterocytes; Epithelial; Epithelial Cells; Epithelium; Event; Evolution; Fluorescence Microscopy; Future; Gall Bladder Diseases; Genes; Goals; Grant; Growth; Growth and Development function; Homeostasis; Human; Human body; Image; Immunofluorescence Immunologic; Immunohistochemistry; Impaired wound healing; Impairment; In Vitro; Intestinal Absorption; Intestines; Investigation; Knockout Mice; Lead; Life; Malignant Neoplasms; Mediating; Membrane; Membrane Protein Traffic; Membrane Proteins; Micronutrients; Molecular; Monomeric GTP-Binding Proteins; Mus; Nature; Nutrient; Organelles; Outcome; Pathogenesis; Personal Satisfaction; Physiological; Physiology; Pilot Projects; Play; Process; Proteins; Publications; RNA; Regulation; Research Design; Research Personnel; Retrieval; Role; Scurvy; Small Interfering RNA; Small Intestines; Sodium; Source; Structure; Testing; Time; Tissues; Transport Process; Tubular formation; Vasomotor; Vesicle; Vitamins; Water; Western Blotting; Work; absorption; apical membrane; base; bone; career; cell motility; cellular microvillus; fluorophore; imaging modality; in vivo; intestinal epithelium; knock-down; link protein; mutant; protein function; public health relevance; red fluorescent protein; small hairpin RNA; trafficking; uptake

DESCRIPTION (provided by applicant): The main aim of this proposal is to allow the principle investigator to become more independent and to perform a pilot study in the area of cell biology with an emphasis on the membrane targeting and trafficking of vitamin C transporter and to generate additional publications and data for future grants. Vitamin C (ascorbic acid) is essential for normal human growth and development. Human intestine and other tissues express two sodium-dependent vitamin C transporters (hSVCT1 and -2). Recent studies have shown the involvement of specific Rab proteins in the membrane targeting/localization, trafficking and function of membrane proteins in intestinal cells. To date, nothing is known about the role of Rab proteins in cell biology and transport physiological aspects of hSVCT1 with specific regards to membrane targeting/localization, trafficking and function in human enterocytes. Recent studies have shown that the alteration in membrane targeting and trafficking events may affect the polarized expression of the given transporters and lead to overall impaired absorption/secretion in epithelia. Further, these cellular events were found to play an important role in the regulation of certain transport processes via insertion/retrieval of the involved transporters to and from the cell membrane. Therefore, studies aimed at regulators such as Rab proteins in membrane targeting and trafficking of transport proteins are of great significance and of cell biological/physiological importance. Recent studies have shown the involvement of Rab8a and 11a in the membrane targeting and trafficking of transport proteins in intestinal epithelial cells and also linked the proteins to human intestinal microvillus inclusion disease. Our specific aim is to determine the role of Rab8a and 11a proteins in polarized membrane targeting/localization, trafficking and function of hSVCT1 in vitro using human enterocytes and confirm results in vivo using Rab8a knockout mice. In these investigations we will use a combination of cell/biochemical/molecular biological and imaging methods. Outcome of these investigations will not only provide the applicant an opportunity to reach his career goals but also contribute to enhance the understanding of the cell biology of hSVCT1 and also other micronutrient transporters. PUBLIC HEALTH RELEVANCE: Vitamin C is an essential nutrient for human well-being and cannot be synthesized, obtains it from diet via intestinal absorption. Human intestine plays a role in regulating and maintaining body vitamin C homeostasis, studies on the cell biology/physiology of its transporters in intestinal cells are important. Outcome of these investigations will assist us to optimize intestinal vitamin C levels in deficiency and sub-optimal levels.

描述（由申请人提供）： 该提案的主要目的是让主要研究者变得更加独立，并在细胞生物学领域进行试点研究，重点是维生素 C 转运蛋白的膜靶向和运输，并为未来的资助提供更多出版物和数据。维生素 C（抗坏血酸）对于人体正常生长和发育至关重要。人类肠道和其他组织表达两种钠依赖性维生素 C 转运蛋白（hSVCT1 和 -2）。最近的研究表明，特定的 Rab 蛋白参与肠细胞膜蛋白的膜靶向/定位、运输和功能。迄今为止，对于 Rab 蛋白在细胞生物学和 hSVCT1 运输生理方面的作用，特别是在人类肠细胞中的膜靶向/定位、运输和功能方面，我们还一无所知。最近的研究表明，膜靶向和运输事件的改变可能会影响特定转运蛋白的极化表达，并导致上皮吸收/分泌的整体受损。此外，发现这些细胞事件通过将相关转运蛋白插入细胞膜或从细胞膜收回，在某些转运过程的调节中发挥重要作用。因此，针对膜靶向和转运蛋白运输中的Rab蛋白等调节因子的研究具有重要意义和细胞生物学/生理学意义。最近的研究表明，Rab8a 和 11a 参与肠上皮细胞中转运蛋白的膜靶向和运输，并且还将这些蛋白与人类肠道微绒毛包涵体疾病联系起来。我们的具体目标是在体外使用人肠细胞确定 Rab8a 和 11a 蛋白在 hSVCT1 的极化膜靶向/定位、运输和功能中的作用，并使用 Rab8a 敲除小鼠在体内确认结果。在这些研究中，我们将结合使用细胞/生化/分子生物学和成像方法。这些研究的结果不仅将为申请人提供实现其职业目标的机会，而且有助于增强对 hSVCT1 和其他微量营养素转运蛋白的细胞生物学的理解。 公共健康相关性：维生素 C 是人类健康的必需营养素，无法合成，只能通过肠道吸收从饮食中获取。人体肠道在调节和维持体内维生素C稳态方面发挥着重要作用，对其在肠道细胞中转运蛋白的细胞生物学/生理学研究具有重要意义。这些研究的结果将帮助我们优化肠道维生素 C 水平，以应对缺乏和次优水平。