Islet-1 is required for ventral neuron survival in Xenopus.
Islet-1 is a LIM domain transcription factor involved in several processes of embryonic development. Xenopus Islet-1 (Xisl-1) has been shown to be crucial for proper heart development. Here we show that Xisl-1 and Xisl-2 are differentially expressed in the nervous system in Xenopus embryos. Knock-down of Xisl-1 by specific morpholino leads to severe developmental defects, including eye and heart failure. Staining with the neuronal markers N-tubulin and Xisl-1 itself reveals that the motor neurons and a group of ventral interneurons are lost in the Xisl-1 morphants. Terminal dUTP nick-end labeling (TUNEL) analysis shows that Xisl-1 morpholino injection induces extensive apoptosis in the ventral neural plate, which can be largely inhibited by the apoptosis inhibitor M50054. We also find that over-expression of Xisl-1 is able to promote cell proliferation and induce Xstat3 expression in the injected side, suggesting a potential role for Xisl-1 in the regulation of cell proliferation in co-operation with the Jak-Stat pathway.
Shi
Yu
Y
CAS-Max Planck Junior Scientist Group, State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China.
Zhao
Shuhua
S
Li
Jiejing
J
Mao
Bingyu
B
D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics; D049109:Cell Proliferation; D002470:Cell Survival / Q000235:genetics; D003512:Cyclohexanones / Q000494:pharmacology; D004625:Embryo, Nonmammalian / Q000378:metabolism; D018398:Homeodomain Proteins / Q000235:genetics / Q000502:physiology*; D060850:LIM-Homeodomain Proteins; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D029867:Xenopus Proteins / Q000235:genetics / Q000502:physiology*; D014982:Xenopus laevis / Q000196:embryology* / Q000235:genetics
C456599:2,2'-methylenebis(1,3-cyclohexanedione); D003512:Cyclohexanones; D018398:Homeodomain Proteins; C544173:ISL1 protein, Xenopus; D060850:LIM-Homeodomain Proteins; D009419:Nerve Tissue Proteins; D014157:Transcription Factors; D029867:Xenopus Proteins; C063843:insulin gene enhancer binding protein Isl-1