L3/Lhx8 is involved in the determination of cholinergic or GABAergic cell fate.
The LIM homeobox family of transcription factors is involved in many processes during the development of the mammalian central nerves system. L3, also called Lhx8 (L3/Lhx8), is a recently identified member of the LIM homeobox gene family and is selectively expressed in the medial ganglionic eminence (MGE). Our previous study demonstrated that L3/Lhx8-null mice specifically lacked cholinergic neurons in the basal forebrain. In this study, we reduced L3/Lhx8 function in the murine neuroblastoma cell line, Neuro2a (N2a), using L3/Lhx8-targeted small interfering RNA (siRNA) produced by H1.2 promoter-driven vector. The levels of cholinergic markers per cell were diminished without a reduction in the number of marker-positive cells. Intriguingly, GABAergic marker expression and the number of GABAergic cells were dramatically increased in the differentiating L3/Lhx8-knockdown N2a. These results suggest the possibility that L3/Lhx8 is involved in the determination of transmitter phenotypes (GABAergic or cholinergic cell fate) in a population of neurons during basal forebrain development.
Department of 2nd Anatomy, Faculty of Medicine, Nara Medical University, Kasihara City, Nara, Japan. manabe@naramed-u.ac.jp
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T
Manabe
K
K
Tatsumi
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M
Inoue
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Matsuyoshi
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Makinodan
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Yokoyama
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Wanaka
D000818:Animals; D015152:Blotting, Northern / Q000379:methods; D002452:Cell Count / Q000379:methods; D016923:Cell Death / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects* / Q000502:physiology; D045744:Cell Line, Tumor; D002795:Choline O-Acetyltransferase / Q000378:metabolism*; D000242:Cyclic AMP / Q000494:pharmacology; D004347:Drug Interactions; D005786:Gene Expression Regulation / Q000187:drug effects; D005822:Genetic Vectors / Q000502:physiology; D005968:Glutamate Decarboxylase / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000096:biosynthesis; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D020287:In Situ Nick-End Labeling / Q000379:methods; D007527:Isoenzymes / Q000378:metabolism; D019394:Ki-67 Antigen / Q000378:metabolism; D060850:LIM-Homeodomain Proteins; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D009447:Neuroblastoma; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000096:biosynthesis / Q000494:pharmacology*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013997:Time Factors; D014157:Transcription Factors; D014162:Transfection / Q000379:methods; D014212:Tretinoin / Q000494:pharmacology; D050494:Vesicular Acetylcholine Transport Proteins; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D018398:Homeodomain Proteins; D007527:Isoenzymes; D019394:Ki-67 Antigen; C498504:LHX6 protein, mouse; C112960:LIM homeobox protein 8; D060850:LIM-Homeodomain Proteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; C493460:Slc18a3 protein, mouse; D014157:Transcription Factors; D050494:Vesicular Acetylcholine Transport Proteins; D049452:Green Fluorescent Proteins; D005680:gamma-Aminobutyric Acid; D014212:Tretinoin; D000242:Cyclic AMP; D002795:Choline O-Acetyltransferase; D005968:Glutamate Decarboxylase; C401141:glutamate decarboxylase 2