CAS BI 203 Lecture Notes - Lecture 21: Glycogen, Cytokine, Prostacyclin

• School: Boston University
• Department: Biology
• Course: CAS BI 203
• Professor: Francis Monette

Document Summary

Extracellular matrix and cell interactions (briefly covers chapter 15) Each organ = millions-billions of cells held together and organized by: cell-extracellular matrix (ecm) interactions, cell-cell interactions. Ecm is composed of a complex mixture of proteins (collagen) and polysaccharides. Fibroblasts secrete many of the necessary proteins for the extracellular matrix: one of the first cells to act when you have a cut. Note: fibroblasts play a key role in tissue maintenance and repair by secreting and maintaining the ecm. Cells have cell surface proteins that attach to the ecm. Integrins = large protein family consisting of several different alpha and beta subunits: differenced in extracellular domain sequences differences in ecm component interactions. Small intracellular domains of the integrins interact with the cytoskeleton provides structural strength to the cell-ecm interaction. Some integrins interact with actin filaments cell-ecm (cid:272)o(cid:374)ta(cid:272)t sites (cid:272)alled (cid:862)focal adhesions(cid:863) Other integrins interact with intermediate filaments cell-ecm contact sites called (cid:862)hemidesmosomes(cid:863).