Tissue-specific expression of two alternatively spliced isoforms of the human insulin receptor protein.
Two insulin receptor mRNA species are expressed in human tissues as a result of alternative splicing of exon 11. This event is regulated in a tissue-specific manner. To date, there is little information about the relative abundance of the two receptor protein isoforms on the cell surface. The aim of the present investigation was to assess whether the tissue-specific expression of the two insulin receptor mRNA species is paralleled by a similar pattern of expression of the two receptor protein isoforms. To this end, we assessed the relative distribution of the two receptor variants in various human tissues at the mRNA and protein levels. A PCR-based technique was used to measure the relative abundance of the two mRNA species, and two immunological assays were used to measure the relative steady-state expression of the two receptor protein isoforms. The expression of the two insulin receptor protein isoforms followed the tissue-specific pattern of expression of the two mRNA species.
Sesti
G
G
Department of Internal Medicine, University of Rome Tor Vergata, Italy.
Tullio
A N
AN
D'Alfonso
R
R
Napolitano
M L
ML
Marini
M A
MA
Borboni
P
P
Longhi
R
R
Albonici
L
L
Fusco
A
A
Aglianò
A M
AM
D016475:3T3 Cells; D000273:Adipose Tissue / Q000378:metabolism; D017398:Alternative Splicing; D000818:Animals; D001323:Autoantibodies / Q000502:physiology; D001483:Base Sequence; D006528:Carcinoma, Hepatocellular; D002294:Carcinoma, Squamous Cell; D002460:Cell Line; D017931:DNA Primers; D005260:Female; D015870:Gene Expression; D006801:Humans; D007003:Hypoglycemia / Q000235:genetics / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008180:Lupus Erythematosus, Systemic / Q000235:genetics / Q000378:metabolism; D008214:Lymphocytes / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D009928:Organ Specificity; D010920:Placenta / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D011972:Receptor, Insulin / Q000096:biosynthesis* / Q000276:immunology; D014407:Tumor Cells, Cultured
D001323:Autoantibodies; D017931:DNA Primers; D012333:RNA, Messenger; D011972:Receptor, Insulin