EXPRESSION OF THYROID HORMONE RECEPTOR mRNA DURING THE HUMAN BRAIN DEVELOPMENT / 解剖学报

ABSTRACT

Objective To observe the variations of thyroid hormone receptors(RTs) mRNA experession during the human brain devlopment. Methods We investigated the ontogeny of TR isoforms in the first and second trimester human fetal different brain areas by semi-quantitative reverse transcriptase-polymerase chain reaction analysis. When we amplified the TR? 2 by PCR, the other sequence was amplified at the same time, it is about 100pb less than the RT? 2, so we cloned it into pGEM-T easy vector to determine its sequence. Results In the first and second trimester human fatal brain, RTs mRNAs were detected in cerebrum, cerebellum, brain, stem, hippocampus, spinal cord, thalamus. TRs mRNAs were relatively higher in cerebrum, cerebellum, hippocampus. In the first trimester human fatal brain, the TR? isoforms mRNAs were higher than TR? 1, In the second trimester human fatal brain, the TR? 2 and TR? 1 were higher than TR? 1. An additional truncated species was detected with the TR? 2 primer set. We submitted its sequencing results to Genbank, comparing it with TR? 2 by BLAST software, the results showed that it is identical to TR? 2 with the exception that it is missing 42 amino acids at 371-412 of TR? 2 sequence, so it is the human TR? 3. At the same time we acquired the Genbank accession number AF522368. Conclusion The spatial and temporal expressions of TR isoforms mRNAs exist in CNS development. We firstly assure the different sequence between human TR?2 and TR?3.