S. Sashihara et al., ORPHAN NUCLEAR RECEPTOR ROR-ALPHA GENE - ISOFORM-SPECIFIC SPATIOTEMPORAL EXPRESSION DURING POSTNATAL-DEVELOPMENT OF BRAIN, Molecular brain research, 42(1), 1996, pp. 109-117
We analyzed expression of mouse orphan nuclear receptor ROR alpha duri
ng postnatal development of rodent brain. Using a riboprobe correspond
ing to the 3'-end of mROR alpha cDNA, a peak of ROR alpha expression w
as observed at postnatal 16 day (P16) in the Purkinje cells of cerebel
lum, neurons of the thalamus and the olfactory bulb. The hippocampus w
as also shown to express ROR alpha with an earlier peak at P7. Express
ion in cell types other than the Purkinje cells appeared transient, On
the other hand, when a probe to the 5'-end of mROR alpha cDNA was use
d, we observed patterns of ROR alpha expression that are different fro
m those observed with the 3'-probe, No specific transcripts of ROR alp
ha were detected with the 5'-probe in the Purkinje cells until P16. Ad
ditionally, the relative level of the hybridization signals with the 5
'-probe and the 3'-probe were different among the various brain region
s. Together with the previous findings that ROR alpha comprises at lea
st four isoforms which differ from one another in their N-terminal reg
ions, these observations suggest that the spatiotemporal expression of
ROR alpha is under isoform-specific regulation. The timing of its exp
ression suggests that ROR alpha may be involved in regulation of postn
atal maturation of specific classes of neurons.