tailieunhanh - Báo cáo sinh học: "Q&A: Quantitative approaches to planar polarity and tissue organization"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Q&A: Quantitative approaches to planar polarity and tissue organization. | Journal of Biology Question Answer Q A Quantitative approaches to planar polarity and tissue organization Emily Marcinkevicius Rodrigo Fernandez-Gonzalez and Jennifer A Zallen Address Howard Hughes Medical Institute and the Developmental Biology Program Sloan-Kettering Institute 1275 York Avenue New York NY 10065 USA. Correspondence Jennifer A Zallen. Email zallenj@ What is cell polarity Polarity in physics is defined as that quality or condition of a body in virtue of which it exhibits opposite or contrasted properties or powers in opposite or contrasted parts or directions 1 . Examples of polarized physical systems include magnets and batteries. In biology polarity refers to the asymmetric distribution of subcellular components resulting in an asymmetric cell morphology behavior or function. In other words in a polarized cell one region looks or acts differently from other regions of the cell. Prominent examples of polarized cell types are neurons and epithelial cells. What is planar cell polarity Epithelial tissues are monolayers of cells that serve as barriers between different environments. Epithelia display two types of polarity apical-basal polarity and planar cell polarity PCP also called tissue polarity . Apical-basal polarity refers to the asymmetry of epithelial cells along their cross-sectional axis with the apical surface facing the external environment or lumen of a tissue and the basal surface contacting other cells Figure 1a . Because of the barrier function of epithelia the apical surface of an epithelial monolayer encounters a different environment than the basal surface. These two compartments have specialized properties that allow them to function in their respective contexts. For example the apical surface of the intestine secretes enzymes into the lumen to aid in digestion and pumps ions to regulate lumen acidity while the basal surface contains proteins that facilitate interactions with the underlying extracellular matrix. Planar .