TY - JOUR
T1 - Molecular cloning of trkE, a novel trk-related putative tyrosine kinase receptor isolated from normal human keratinocytes and widely expressed by normal human tissues
AU - Di Marco, Eddi
AU - Cutuli, Nunzio
AU - Guerra, Liliana
AU - Cancedda, Ranieri
AU - De Luca, Michele
PY - 1993/11/15
Y1 - 1993/11/15
N2 - We have identified and cloned a new member of the trk gene family, termed trkE, -which generates a 3.9-kilobase (kb) transcript in normal human keratinocytes and in a variety of normal human tissues, but not in liver. Albeit at low level, trkE transcript is expressed also by PC 12 cells. The open reading frame codes for a polypeptide of 876 amino acids exhibiting the classic features of cell surface tyrosine protein kinases. trkE catalytic domain is 41% identical to trkA and shows several features unique to the trk gene family. Its extracellular domain does not show significant homology to any known proteins. trkE is the first member of this gene family found abundantly and widely expressed in normal human tissues. Several lines of evidence suggest that NGF is also the ligand for trkE; (i) normal human keratinocytes bind NGF with high affinity, (ii) NGF stimulates keratinocyte growth in an autocrine fashion, (iii) NGF exerts its biological effect on keratinocytes through the stimulation of a trk-specific tyrosine kinase, and (iv) keratinocytes lack trkA but do express large amount of trkE. trkE might also be the NGF receptor by other human peripheral tissues, such as pancreatic islets, and might represent a non-neuronal receptor for this ligand.
AB - We have identified and cloned a new member of the trk gene family, termed trkE, -which generates a 3.9-kilobase (kb) transcript in normal human keratinocytes and in a variety of normal human tissues, but not in liver. Albeit at low level, trkE transcript is expressed also by PC 12 cells. The open reading frame codes for a polypeptide of 876 amino acids exhibiting the classic features of cell surface tyrosine protein kinases. trkE catalytic domain is 41% identical to trkA and shows several features unique to the trk gene family. Its extracellular domain does not show significant homology to any known proteins. trkE is the first member of this gene family found abundantly and widely expressed in normal human tissues. Several lines of evidence suggest that NGF is also the ligand for trkE; (i) normal human keratinocytes bind NGF with high affinity, (ii) NGF stimulates keratinocyte growth in an autocrine fashion, (iii) NGF exerts its biological effect on keratinocytes through the stimulation of a trk-specific tyrosine kinase, and (iv) keratinocytes lack trkA but do express large amount of trkE. trkE might also be the NGF receptor by other human peripheral tissues, such as pancreatic islets, and might represent a non-neuronal receptor for this ligand.
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M3 - Article
C2 - 8226977
AN - SCOPUS:0027437634
VL - 268
SP - 24290
EP - 24295
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 32
ER -