RESUMO

Protein food modulates the activity of proteases of the midgut gland of Penaeus vannamei. Shrimp fed with food containing 15, 30 and 50% protein exhibited differences in trypsin and chymotrypsin activity and trypsin mRNA levels. Shrimp fed with 30% protein showed higher trypsin and chymotrypsin activities than those fed 15 or 50% protein. An additional paralogue trypsin was observed with electrophoretic analysis in shrimp fed 30% protein. Shrimp fed 30% protein showed the highest trypsin to mRNA concentration, suggesting that trypsin genes expression is regulated transcriptionally.

Assuntos

Proteínas Alimentares/farmacologia , Sistema Digestório/enzimologia , Penaeidae/enzimologia , Tripsina/metabolismo , Animais , Peso Corporal , Quimotripsina/análise , Quimotripsina/biossíntese , Regulação da Expressão Gênica , Tamanho do Órgão , Penaeidae/anatomia & histologia , Penaeidae/genética , RNA Mensageiro/metabolismo , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Tripsina/biossíntese , Tripsina/genética