Lecture 16 Epithelial Transport and Glucose Uptake

Lecture 16 Epithelial Transport and Glucose Uptake - IPHY...

Info iconThis preview shows pages 1–20. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: IPHY 3060 Lecture 17: Epithelial Transport and Glucose Uptake Epithelial cells form sheets lining body surfaces Epithelium lines the body Blood vessels Outside of bodyskin Respiratory tract GI tract Reproductive tract Any other ducts, organs, tracts, etc. 2 Main Functions of Epithelial Layers: To serve as a protective barrier To selectively transport specific substances across this barrier Key Point #1: Epithelial cells are polarizedthe two sides are not identical Epithelial Cells are Polarized Apical side faces into lumen Basolateral side faces away from lumen Lumen of vessel, duct, or tube Apical Side Basolateral Side Epithelial Layers, Cell-Cell Adhesions, and Protective Barriers Key Point #2: Cell-cell adhesions between epithelial cells help to form a tight protective barrier Cell-Cell Adhesions: Protein connections between cells 3 Types of Cell-Cell Adhesions in Epithelial Cells Tight Junctions stitches Adherens Junctions patches Desmosomes rivets Tight junction Adherens junction Desmosome Tight Junctions Transmembrane stitches or zippers that seal adjacent epithelial cells together Tight Junctions Located just below the apical membrane Stitches or zippers are transmembrane proteins on both cells that bind together to sew or zip membranes of adjacent cells together Function is to restrict apical to basolateral diffusion between cells by stitching membranes of adjacent epithelial cells together Tight Junctions Tight Junction Proteins Occludin Claudins JAMs Adherens Junctions Found just below tight junctions Consist of protein-protein patches sewn together to bind cells Function is to bind cells to cells and serve as anchor sites for connection of actin cytoskeleton to cell membrane; do NOT restrict apical-basolateral diffusion Adherens junction Adherens Junctions Proteins Cadherins calcium-dependent transmembrane proteins Catenins bind cadherins to actin filaments Desmosomes Found on basolateral membrane Like rivets that link adjacent epithelial cells Main functions are bind cells to cells and to matrix and to provide structural integrity to tissues by linking intermediate filament cytoskeletons of adjacent cells Desmosome Desmosome Proteins Desmocollins and desmogleins special cadherins Plakoglobins and desmoplakins link desmogleins and desmocollins to intermediate filaments Movement of Substances Across Epithelial Layers Cell-cell adhesions between epithelial cells...
View Full Document

Page1 / 60

Lecture 16 Epithelial Transport and Glucose Uptake - IPHY...

This preview shows document pages 1 - 20. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online