LIM-Homeodomain Transcription Factor LHX4 Is Required for the Differentiation of Retinal Rod Bipolar Cells and OFF-Cone Bipolar Subtypes

We describe the direct and cell-specific regulation of the Drosophila FMRFa neuropeptide gene by Apterous, a LIM homeodomain transcription factor. dFMRFa and Apterous are expressed in partially overlapping subsets of neurons, including two of the seventeen dFMRFa cell types, the Tv neuroendocrine cells and the SP2 interneurons. Apterous contributes to the initiation of dFMRFa expression in Tv neurons, but not in those dFMRFa neurons that do not express Apterous. Apterous is not required for Tv neuron survival or morphological differentiation. Apterous contributes to the maintenance of dFMRFa expression by postembryonic Tv neurons, although the strength of its regulation is diminished. Apterous regulation of dFMRFa expression includes direct mechanisms, although ectopic Apterous does not induce ectopic dFMRFa. These findings show that, for a subset of neurons that share a common neurotransmitter phenotype, the Apterous LIM homeoprotein helps define neurotransmitter expression with very limited effects on other aspects of differentiation.

Download Full-text

Cofactor CLIM2 promotes the repressive action of LIM homeodomain transcription factor Lhx2 in the expression of porcine pituitary glycoprotein hormone α subunit gene

Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression ◽

10.1016/j.bbaexp.2006.08.004 ◽

2006 ◽

Vol 1759 (8-9) ◽

pp. 403-409 ◽

Cited By ~ 8

Author(s):

Takao Susa ◽

Takanobu Sato ◽

Tetsuo Ono ◽

Takako Kato ◽

Yukio Kato

Keyword(s):

Transcription Factor ◽

Subunit Gene ◽

Glycoprotein Hormone ◽

Α Subunit ◽

Homeodomain Transcription Factor ◽

Lim Homeodomain

Download Full-text

GABAA, GABACand glycine receptor-mediated inhibition differentially affects light-evoked signalling from mouse retinal rod bipolar cells

The Journal of Physiology ◽

10.1113/jphysiol.2005.103648 ◽

2006 ◽

Vol 572 (1) ◽

pp. 215-225 ◽

Cited By ~ 77

Author(s):

Erika D. Eggers ◽

Peter D. Lukasiewicz

Keyword(s):

Glycine Receptor ◽

Bipolar Cells ◽

Retinal Rod ◽

Rod Bipolar Cells

Download Full-text

LIM-Homeodomain Transcription Factor Isl-1 Mediates Kisspeptin's Effect on Insulin Secretion in Mice

Molecular Endocrinology ◽

10.1210/me.2013-1410 ◽

2014 ◽

Vol 28 (8) ◽

pp. 1276-1290 ◽

Cited By ~ 8

Author(s):

Juan Chen ◽

Rui Fu ◽

Yan Cui ◽

Jirong Pan ◽

Yushan Li ◽

...

Keyword(s):

Transcription Factor ◽

Insulin Secretion ◽

Pancreatic Islet ◽

Islet Cells ◽

Direct Action ◽

Janus Kinase ◽

Homeodomain Transcription Factor ◽

Lim Homeodomain

Kisspeptin and the G protein-coupled receptor 54 (GPR54) are highly abundant in the pancreas. In addition, circulating kisspeptin directly influences insulin secretion through GPR54. However, the mechanisms by which kisspeptin affects insulin release are unclear. The LIM-homeodomain transcription factor, Isl-1, is expressed in all pancreatic islet cells and is involved in regulating both islet development and insulin secretion. We therefore investigated potential interactions between kisspeptin and Isl-1. Our results demonstrate that Isl-1 and GPR54 are coexpressed in mouse pancreatic islet β-cells and NIT cells. Both in vitro and in vivo results demonstrate that kisspeptin-54 (KISS-54) inhibits Isl-1 expression and insulin secretion and both the in vivo and in vitro effects of KISS-54 on insulin gene expression and secretion are abolished when an Isl-1-inducible knockout model is used. Moreover, our results demonstrate that the direct action of KISS-54 on insulin secretion is mediated by Isl-1. Our results further show that KISS-54 influences Isl-1 expression and insulin secretion through the protein kinase C-ERK1/2 pathway. Conversely, insulin has a feedback loop via the Janus kinase-phosphatidylinositol 3-kinase pathway regulating kisspeptin expression and secretion. These findings are important in understanding mechanisms of insulin secretion and metabolism in diabetes.

Download Full-text