Different IGF-I Isoforms Expressed in Muscle
نویسنده
چکیده
analysis showed that this was a splice variant of the insulin-like growth factor-I (IGF-I) gene, although its 3 exons were different from the liver or systemic type of IGF-I. However, it was noted that muscle also expresses the systemic type of IGF-I (IGF-IEa). The terminology for the IGF-I variants is a problem when attempting to apply it to nonhepatic tissues and to different species. Also, we encountered a further problem with the hepatic IGF-I terminology, because the variant we discovered would be classified as IGF-IEb in the rat but IGF-IEc in the human (14). It became apparent that the muscle IGF-I isoforms, although they are derived from the same gene, have to be characterized separately. Therefore, we named this cryptic splice variant mechano growth factor (MGF), because it is expressed in response to mechanical stimulation and has a different carboxy peptide sequence from that of the liver type of IGF-I.
منابع مشابه
Different IGF-I Isoforms Expressed in Muscle
analysis showed that this was a splice variant of the insulin-like growth factor-I (IGF-I) gene, although its 3 exons were different from the liver or systemic type of IGF-I. However, it was noted that muscle also expresses the systemic type of IGF-I (IGF-IEa). The terminology for the IGF-I variants is a problem when attempting to apply it to nonhepatic tissues and to different species. Also, w...
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