Multiple autophosphorylation sites of the epidermal growth factor receptor are essential for receptor kinase activity and internalization. Contrasting significance of tyrosine 992 in the native and truncated receptors.

A Sorkin; K Helin; C M Waters; G Carpenter; L Beguinot

Multiple autophosphorylation sites of the epidermal growth factor receptor are essential for receptor kinase activity and internalization. Contrasting significance of tyrosine 992 in the native and truncated receptors.

A Sorkin, K Helin, C M Waters, G Carpenter, L Beguinot

Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › peer review

150 Citationer (Scopus)

Abstract

Udgivelsesdato: 1992-Apr-25

Originalsprog	Engelsk
Tidsskrift	Journal of Biological Chemistry
Vol/bind	267
Udgave nummer	12
Sider (fra-til)	8672-8
Antal sider	6
ISSN	0021-9258
Status	Udgivet - 1992

Bibliografisk note

Keywords: Animals; Base Sequence; Blotting, Western; Down-Regulation; Isoenzymes; Mice; Molecular Sequence Data; Mutation; Phosphorylation; Protein-Tyrosine Kinases; Receptor, Epidermal Growth Factor; Type C Phospholipases; Tyrosine

Citationsformater

Multiple autophosphorylation sites of the epidermal growth factor receptor are essential for receptor kinase activity and internalization. Contrasting significance of tyrosine 992 in the native and truncated receptors. / Sorkin, A; Helin, K; Waters, C M et al.
I: Journal of Biological Chemistry, Bind 267, Nr. 12, 1992, s. 8672-8.

Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › peer review

@article{05cce67053ea11dd8d9f000ea68e967b,

title = "Multiple autophosphorylation sites of the epidermal growth factor receptor are essential for receptor kinase activity and internalization. Contrasting significance of tyrosine 992 in the native and truncated receptors.",

abstract = "The role of epidermal growth factor (EGF) receptor autophosphorylation sites in the regulation of receptor functions has been studied using cells transfected with mutant EGF receptors. Simultaneous point mutation of 4 tyrosines (Y1068, Y1086, Y1148, Y1173) to phenylalanine, as well as removal of these sites by truncation of the carboxyl-terminal 123 amino acid residues, resulted in reduced receptor phosphorylation of an in vivo specific substrate phospholipase C-gamma 1 to less than 50% compared to the wild-type receptor. The internalization rate constant Ke was also significantly lower in these mutants (0.15/min) compared to cells transfected with wild-type receptor (0.27/min). Additional mutation of tyrosine 992 to phenylalanine in the truncated receptor mutant (Dc-123F) further decreased the receptor internalization rate to a minimal level (ke = 0.07-0.10/min), equivalent to the ke measured for cells expressing kinase-negative receptor (A721). Moreover, tyrosine kinase activity of the Dc-123F receptor toward phospholipase C-gamma 1, compared to wild-type receptor, was reduced by 90%. Taken together, these results show that EGF receptor lacking five autophosphorylation sites functions similar to a kinase-negative receptor. Mutation of tyrosine residue Y992 alone in the context of full length EGF receptor, however, did not affect receptor internalization or kinase activity toward phospholipase C-gamma 1. These data indicate that tyrosine 992 is critical for substrate phosphorylation and internalization only in the context of the truncated receptor, and that minor autophosphorylation sites, such as Y992, may act as compensatory regulatory sties in the absence of the major EGF receptor autophosphorylation sites.",

author = "A Sorkin and K Helin and Waters, {C M} and G Carpenter and L Beguinot",

note = "Keywords: Animals; Base Sequence; Blotting, Western; Down-Regulation; Isoenzymes; Mice; Molecular Sequence Data; Mutation; Phosphorylation; Protein-Tyrosine Kinases; Receptor, Epidermal Growth Factor; Type C Phospholipases; Tyrosine",

year = "1992",

language = "English",

volume = "267",

pages = "8672--8",

journal = "Journal of Biological Chemistry",

issn = "0021-9258",

publisher = "American Society for Biochemistry and Molecular Biology, Inc.",

number = "12",

}

TY - JOUR

T1 - Multiple autophosphorylation sites of the epidermal growth factor receptor are essential for receptor kinase activity and internalization. Contrasting significance of tyrosine 992 in the native and truncated receptors.

AU - Sorkin, A

AU - Helin, K

AU - Waters, C M

AU - Carpenter, G

AU - Beguinot, L

N1 - Keywords: Animals; Base Sequence; Blotting, Western; Down-Regulation; Isoenzymes; Mice; Molecular Sequence Data; Mutation; Phosphorylation; Protein-Tyrosine Kinases; Receptor, Epidermal Growth Factor; Type C Phospholipases; Tyrosine

PY - 1992

Y1 - 1992

N2 - The role of epidermal growth factor (EGF) receptor autophosphorylation sites in the regulation of receptor functions has been studied using cells transfected with mutant EGF receptors. Simultaneous point mutation of 4 tyrosines (Y1068, Y1086, Y1148, Y1173) to phenylalanine, as well as removal of these sites by truncation of the carboxyl-terminal 123 amino acid residues, resulted in reduced receptor phosphorylation of an in vivo specific substrate phospholipase C-gamma 1 to less than 50% compared to the wild-type receptor. The internalization rate constant Ke was also significantly lower in these mutants (0.15/min) compared to cells transfected with wild-type receptor (0.27/min). Additional mutation of tyrosine 992 to phenylalanine in the truncated receptor mutant (Dc-123F) further decreased the receptor internalization rate to a minimal level (ke = 0.07-0.10/min), equivalent to the ke measured for cells expressing kinase-negative receptor (A721). Moreover, tyrosine kinase activity of the Dc-123F receptor toward phospholipase C-gamma 1, compared to wild-type receptor, was reduced by 90%. Taken together, these results show that EGF receptor lacking five autophosphorylation sites functions similar to a kinase-negative receptor. Mutation of tyrosine residue Y992 alone in the context of full length EGF receptor, however, did not affect receptor internalization or kinase activity toward phospholipase C-gamma 1. These data indicate that tyrosine 992 is critical for substrate phosphorylation and internalization only in the context of the truncated receptor, and that minor autophosphorylation sites, such as Y992, may act as compensatory regulatory sties in the absence of the major EGF receptor autophosphorylation sites.

AB - The role of epidermal growth factor (EGF) receptor autophosphorylation sites in the regulation of receptor functions has been studied using cells transfected with mutant EGF receptors. Simultaneous point mutation of 4 tyrosines (Y1068, Y1086, Y1148, Y1173) to phenylalanine, as well as removal of these sites by truncation of the carboxyl-terminal 123 amino acid residues, resulted in reduced receptor phosphorylation of an in vivo specific substrate phospholipase C-gamma 1 to less than 50% compared to the wild-type receptor. The internalization rate constant Ke was also significantly lower in these mutants (0.15/min) compared to cells transfected with wild-type receptor (0.27/min). Additional mutation of tyrosine 992 to phenylalanine in the truncated receptor mutant (Dc-123F) further decreased the receptor internalization rate to a minimal level (ke = 0.07-0.10/min), equivalent to the ke measured for cells expressing kinase-negative receptor (A721). Moreover, tyrosine kinase activity of the Dc-123F receptor toward phospholipase C-gamma 1, compared to wild-type receptor, was reduced by 90%. Taken together, these results show that EGF receptor lacking five autophosphorylation sites functions similar to a kinase-negative receptor. Mutation of tyrosine residue Y992 alone in the context of full length EGF receptor, however, did not affect receptor internalization or kinase activity toward phospholipase C-gamma 1. These data indicate that tyrosine 992 is critical for substrate phosphorylation and internalization only in the context of the truncated receptor, and that minor autophosphorylation sites, such as Y992, may act as compensatory regulatory sties in the absence of the major EGF receptor autophosphorylation sites.

M3 - Journal article

C2 - 1314835

SN - 0021-9258

VL - 267

SP - 8672

EP - 8678

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

IS - 12

ER -