论文部分内容阅读
Many actin-binding proteins are expressed in eukaryotic cells.These polypep-tides assist in stabilizing and rearranging the organization of the actin cytoskel-eton in response to external stimuli,or during cell migration and adhesion.Herewe review a particular set of actin-binding proteins called plastins.Plastins(alsocalled fimbrins)belong to a subclass of actin-binding proteins known as actinbundling proteins.Three isoforms have been characterized in mammals:T-plastinis expressed in cells from solid tissue,whereas L-plastin occurs predominantly inhematopoietic cells.The third isoform,I-plastin,is specifically expressed in thesmall intestine,colon and kidney.These proteins share the unique property ofcross-linking actin filaments into fight bundles.Although plastins are primarilyinvolved in regulation of the actin cytoskeleton,they possess some uniquefeatures.For instance,they are implicated in invasion by pathogenic bacteriasuch as Shigellaflexneri and Salmonella typhimurium.Also,L-plastin plays animportant role in leukocyte function.T-plastin,on the other hand,is possiblyinvolved in DNA repair.Finally,both T-and L-plastin are implicated in severaldiseases,and L-plastin is considered to be a valuable marker for cancer.
Many actin-binding proteins are expressed in eukaryotic cells. The polypept-tides assist in stabilizing and rearranging the organization of the actin cytoskel-eton in response to external stimuli, or during cell migration and adhesion. Herewe review a particular set of actin-binding proteins called plastins. Plastins (alsocalled fimbrins) belong to a subclass of actin-binding proteins known as actinbundling proteins. Of is oforms have been characterized in mammals: T-plastinis expressed in cells from solid tissue, whereas L-plastin occurs predominantly in hematopoietic cells. The third isoform, I-plastin, is specifically expressed in the small intestine, colon and kidney. These proteins share the unique property of cross-linking actin filaments into fight bundles. Although plastins are primarily in regulation in the actin cytoskeleton, they possess some unique features. For instance, they are implicated in invasion by pathogenic bacteriasuch as Shigella flexneri and Salmonella typhimurium. Also, Lp lastin plays animportant role in leukocyte function. T-plastin, on the other hand, is possibly in viral repair. Notably, both T-and L-plastin are implicated in several diseases, and L-plastin is considered to be a precious marker for cancer .