Processing and secretion of rat alpha 1-microglobulin-bikunin expressed in eukaryotic cell lines.
The precursor protein alpha 1-microglobulin-bikunin was cleaved to the same degree whether expressed in CHO cells or in mutated CHO cells, RPE.40 cells, suggested to lack a functional form of the intracellular protease furin. Thus, alpha 1-microglobulin-bikunin probably is not cleaved in vivo by furin. However, simultaneous overexpression of the precursor and furin in COS, CHO and RPE.40 cells increased the cleavage, suggesting that compartmentalisation and concentrations of protease and precursor are important for the cleavage, besides the in vitro specificity. Expression of alpha 1-microglobulin and bikunin alone gave different protein patterns of SDS-PAGE as compared to expression of the precursor and subsequent cleavage, suggesting that the precursor protein is important for the post-translational handling of alpha 1-microglobulin and bikunin.
Bratt
T
T
Department of Medical and Physiological Chemistry, Lund University, Sweden.
Cedervall
T
T
Akerström
B
B
D000510:Alpha-Globulins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001483:Base Sequence; D016466:CHO Cells; D006224:Cricetinae; D045683:Furin; D015870:Gene Expression; D006023:Glycoproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008562:Membrane Glycoproteins; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011480:Protease Inhibitors / Q000378:metabolism*; D011498:Protein Precursors / Q000235:genetics / Q000378:metabolism*; D011499:Protein Processing, Post-Translational / Q000502:physiology*; D051381:Rats; D013381:Subtilisins / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D014360:Trypsin Inhibitor, Kunitz Soybean
D000510:Alpha-Globulins; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D011480:Protease Inhibitors; D011498:Protein Precursors; C109148:SPINT2 protein, human; C016001:alpha-1-microglobulin; D014360:Trypsin Inhibitor, Kunitz Soybean; D013381:Subtilisins; D045683:Furin