The role of insulin receptor signaling in zebrafish embryogenesis.
Insulin receptor (IR) signaling is considered to be important in growth and development in addition to its major role in metabolic homeostasis. The metabolic role of insulin in carbohydrate and lipid metabolism is extensively studied. In contrast, the role of IR activation during embryogenesis is less understood. To address this, we examined the function of the IR during zebrafish development. Zebrafish express two isoforms of IR (insra and insrb). Both isoforms were cloned and show high homology to the human insulin receptor and can functionally substitute for the human IR in fibroblasts derived from insr gene-deleted mice. Gene expression studies reveal that these receptors are expressed at moderate levels in the central nervous system during development. Morpholino-mediated selective knockdown of each of the IR isoforms causes growth retardation and profound morphogenetic defects in the brain and eye. These results clearly demonstrate that IR signaling plays essential roles in vertebrate embryogenesis and growth.
Toyoshima
Yuka
Y
Division of Endocrinology, Diabetes, and Bone Disease, Mount Sinai School of Medicine, New York, New York 10029, USA.
Monson
Christopher
C
Duan
Cunming
C
Wu
Yingjie
Y
Gao
Chuan
C
Yakar
Shoshana
S
Sadler
Kirsten C
KC
LeRoith
Derek
D
D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D051379:Mice; D009154:Mutation; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D011972:Receptor, Insulin / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology*; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics
D020033:Protein Isoforms; D011972:Receptor, Insulin