|Budget Amount *help
¥2,600,000 (Direct Cost : ¥2,600,000)
Fiscal Year 1996 : ¥1,300,000 (Direct Cost : ¥1,300,000)
Fiscal Year 1995 : ¥1,300,000 (Direct Cost : ¥1,300,000)
1. Three species of cDNA encoding AREC3/Six4 protein has been cloned from mouse skeletal muscle cDNA library. Sequence analysis revealed that the AREC3 is a member of new gene family of Six which has homeodomain and sixdomain as conserved domains. Both of the domains are necessary for specific DNA binding, and potential transactivation domain resides in the C terminal portion. During the differentiation of myoblast cell line C2C12, the productio of AREC3 protein is induced in the cytoplasm. During postnatal retina formation in rat, the expression pattern of the gene product varies dramatically. These observations suggest that the gene is involved in development and differentiation process.
2. Other members of Six family genes, Six2, Six3 and Six5 cDNAs were isolated from mouse retina cDNA library. These genes were shown to be expressed in retina by in situ hybridization. Homeodomain and sixdomain function as a specific DNA binding domain, and the DNA binding specificity was conserved am
ong Six2, Six4 and Six5.
3. The distribution of AREC3 protein was analyzed by immunohistochemistry in newborn the rat retina and in the adult rat brain. In PND (postnatal day)1, the AREC3 resided in the nucleus of ganglion cells, in PND4, in addition to PND1, the protein was expressed in the inner nuclear layr and in PND7, the expression was observed in outer cells of the inner nuclear layr. In PND13, the expression was moved from the nucleus to the cytoplasm in ganglion cells, and the protein was expressed in outer segment and inner segment. After PND20, no distribution in the nucleus was observed. In rat brain, AREC3 protein was observed in the cell nucleus in hippocampus and in the piriform cortex and the mRNA was observed in the cytoplasm.
4. In the mouse embryo, the AREC3 protein was detected in the nucleus of neuronal cells from stage E9.5. The production peaks at E10.5 to E11.5 and then gradually declined to undetectable level at E14.5
These results indicates that the AREC3 plays an important role in differentiation and development of neuron and retina. Less