Jl. Frendo et al., AN ISOFORM OF THE HUMAN CALCITONIN RECEPTOR IS EXPRESSED IN TT CELLS AND IN MEDULLARY CARCINOMA OF THE THYROID, FEBS letters, 342(2), 1994, pp. 214-216
We amplified, using the polymerase chain reaction and calcitonin recep
tor (CTR) specific primers, RNA extracted from medullary thyroid carci
noma (MTC) and the derived TT cell line. Both secrete large amounts of
calcitonin. Electrophoresis of amplification products revealed, in bo
th cases, an ethidium bromide-stained band that hybridized to a CTR pr
obe. Sequencing the band amplified from TT cells revealed an open read
ing frame identical to the sequence of H-CTR but lacking 16 amino acid
s in the first intracellular loop. This demonstrates the existence of
an mRNA coding for a subtype of H-CTR which is expressed in TT cells a
nd MTC.