Tubulin tyrosinolated in vivo can be different from that tyrosinolated in vitro.
Tubulin can be tyrosinolated, in the presence of ATP, by tubulin-tyrosine ligase, and tyrosine can be released by the same enzyme in the presence of ADP plus inorganic phosphate. There is however a 'non-substrate' component of tubulin which can not be tyrosinolated or detyrosinolated by this enzyme. Tubulin tyrosinolated in vivo was found to be the non-substrate species in HeLa cells, and the substrate species in cultured neuronal cells. In this respect HeLa tubulin resembled membrane-associated tubulin from brain, and neuronal cell tubulin resembled brain cytosolic tubulin.
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002268:Carboxypeptidases / Q000378:metabolism; D043422:Carboxypeptidases A; D002460:Cell Line; D002645:Chickens; D005910:Glioma / Q000378:metabolism*; D006367:HeLa Cells / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D009447:Neuroblastoma / Q000378:metabolism*; D010453:Peptide Synthases / Q000378:metabolism; D013379:Substrate Specificity; D014404:Tubulin / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism*
D014404:Tubulin; D014443:Tyrosine; D002268:Carboxypeptidases; D043422:Carboxypeptidases A; D010453:Peptide Synthases; C023213:tyrosyltubulin ligase