cDNA cloning, chromosomal localization and expression pattern analysis of human LIM-homeobox gene LHX4

LHX4 gene is a member of the LIM-homeobox gene family and plays a critical role in the development of motor neurons. We have isolated a cDNA of human LHX4 from a library of the adult human spinal cord. Its sequence is 92% homologous to that of the mouse Lhx4. The genomic structure of the LHX4 gene and its chromosomal localization were determined. The gene was mapped on human chromosome 1q 24.1-1q 24.3 and composed of six exons. The homeodomain was encoded by two exons, exons 4 and 5. The first LIM domain was coded by exon 2, and the second by exon 3. Human MTE Array was used to study the expression profile of LHX4 in 72 human tissues. The expression was specific in the CNS including the fetal brain, the spinal cord, and the cerebral cortex. In situ hybridization of the adult rodent CNS showed the abundant expression of LHX4 in the cerebral cortex and motor neurons of the spinal cord. Our results suggest that LHX4 may play a role in the CNS, especially the neocortex and the spinal cord, and provide a basis to investigate potential involvement of the LHX4 gene in human diseases.