LIM-homeodomain proteins Lhx1 and Lhx5, and their cofactor Ldb1, control Purkinje cell differentiation in the developing cerebellum.
Purkinje cells are one of the major types of neurons that form the neural circuitry in the cerebellum essential for fine control of movement and posture. During development, Purkinje cells also are critically involved in the regulation of proliferation of progenitors of granule cells, the other major type of neurons in the cerebellum. The process that controls differentiation of Purkinje cells from their early precursors is poorly understood. Here we report that two closely related LIM-homeobox genes, Lhx1 and Lhx5, were expressed in the developing Purkinje cells soon after they exited the cell cycle and migrated out of the cerebellar ventricular zone. Double-mutant mice lacking function of both Lhx1 and Lhx5 showed a severe reduction in the number of Purkinje cells. In addition, targeted inactivation of Ldb1, which encodes a cofactor for all LIM-homeodomain proteins, resulted in a similar phenotype. Our studies thus provide evidence that these transcription regulators are essential for controlling Purkinje cell differentiation in the developing mammalian cerebellum.
Laboratory of Mammalian Genes and Development, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-2790, USA.
Yangu
Y
Zhao
Kin-Ming
KM
Kwan
Christina M
CM
Mailloux
Woon-Kyu
WK
Lee
Alexander
A
Grinberg
Wolfgang
W
Wurst
Richard R
RR
Behringer
Heiner
H
Westphal
D000818:Animals; D002454:Cell Differentiation; D002531:Cerebellum / Q000196:embryology*; D004268:DNA-Binding Proteins / Q000502:physiology*; D005260:Female; D018398:Homeodomain Proteins / Q000502:physiology*; D060588:LIM Domain Proteins; D060850:LIM-Homeodomain Proteins; D051379:Mice; D008810:Mice, Inbred C57BL; D009419:Nerve Tissue Proteins / Q000502:physiology*; D011247:Pregnancy; D011689:Purkinje Cells / Q000166:cytology*; D014157:Transcription Factors / Q000502:physiology*
D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D060588:LIM Domain Proteins; D060850:LIM-Homeodomain Proteins; C102084:Ldb1 protein, mouse; C499523:Lhx1 protein, mouse; C102995:Lhx5 protein, mouse; D009419:Nerve Tissue Proteins; D014157:Transcription Factors