RESUMEN

Overlapping cDNA fragments encoding avian cathepsin B were cloned from an osteoclast cDNA library and sequenced. The primary structure of the prepro enzyme deduced from this sequence has 340 amino acids. The mature portion of the enzyme is 80% identical with murine cathepsin B; regions found in other papain superfamily enzymes are conserved. In osteoclasts and cultured macrophages, which produce large quantities of cathepsin B, mRNAs of 1.8 and 2.4 kb are produced in approximately equal quantities, while cells producing smaller quantities of the enzyme produce predominantly the 2.4 kb form. This variation in mRNAs suggests transcriptional differences related to production of large quantities of the enzyme.

Asunto(s)

Catepsina B/genética , ADN Complementario/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Catepsina B/análisis , Pollos , Clonación Molecular , ADN Complementario/química , Datos de Secuencia Molecular , Osteoclastos/enzimología , ARN Mensajero/aislamiento & purificación