Protein @entity669 kinases (PTKs) play a role in regulating the growth and differentiated functions of thyroid cells and are probably involved in tumorigenesis of @entity3557 . To better understand the roles of PTKs in the physiology and pathophysiology of the thyroid, we analyzed the expression profile of receptor-type PTKs in normal @entity1 thyroid tissues. Highly conserved regions in the catalytic domains of receptor-type PTKs were amplified by RT-PCR using degenerate oligonucleotide primers. @entity377 sequencing of about 100 clones identified 21 PTKs, including 16 receptor type and 5 nonreceptor type; no novel PTK was identified. Insulin-like growth factor I receptor, @entity3820 ( @entity3820 ), @entity3819 , @entity14029 , @entity470 , etc., appear to be the most abundant receptor-type PTKs in the thyroid; many of which ( @entity3820 , @entity3819 , @entity14029 , etc.) have never previously been demonstrated to be expressed in the thyroid. The expression of messenger RNAs (mRNAs) for @entity3820 , @entity14029 , and @entity3819 in normal thyroid cells was confirmed by Northern blot analysis, and interestingly, the expression levels of @entity3820 and @entity3819 mRNAs were decreased in all three @entity259 cell lines examined (FRO, WRO, and NPA), whereas @entity14029 mRNA and protein were overexpressed in 2 of 3 @entity259 cell lines (FRO and WRO) compared with that in normal tissue. The @entity14029 gene was, however, neither amplified nor rearranged. The biological activity of the ligand for @entity14029 , the product of @entity27242 ( @entity27242 ), was then evaluated, demonstrating modest mitogenic activity in @entity259 cells overexpressing @entity14029 . Furthermore, @entity27242 mRNA was expressed in FRO cells. Thus, we here identify a variety of PTKs expressed in the thyroid gland, many of which may participate in the regulation of thyroid cell function. Variable expression levels of some PTKs in normal and cancerous cells suggest that there may be an imbalance and disarray of phosphorylation events in @entity259 cells. Furthermore, @entity27242 is identified as a novel growth factor for @entity259 cells overexpressing @entity14029 receptor @entity669 kinase.

Expression profile of receptor-type protein XXXX kinase genes in the @entity1 thyroid.

@entity3557 :: ('MESH:C536915', 'Disease') :: ['papillary-type thyroid carcinoma'] @entity1 :: ('9606', 'Species') :: ['human'] @entity14029 :: ('558', 'Gene') :: ['Axl', 'axl'] @entity470 :: ('1956', 'Gene') :: ['epidermal growth factor receptor'] @entity377 :: ('CHEBI:36976', 'Chemical') :: ['Nucleotide'] @entity3820 :: ('5159', 'Gene') :: ['PDGFR', 'platelet-derived growth factor receptor'] @entity3819 :: ('780', 'Gene') :: ['TrkE', 'trkE'] @entity259 :: ('MESH:D013964', 'Disease') :: ['thyroid carcinoma'] @entity27242 :: ('2621', 'Gene') :: ['growth arrest-specific gene 6', 'gas6', 'Gas6'] @entity669 :: ('CHEBI:18186', 'Chemical') :: ['tyrosine']
@entity669 :: (CHEBI:18186,Chemical) :: ['tyrosine']
