The N-terminal domain of human GABA receptor ρ1 subunits contains signals for homooligomeric and heterooligomeric interaction

Abigail S Hackam, Tian Li Wang, William B. Guggino, Garry R. Cutting

Research output: Contribution to journalArticle

41 Citations (Scopus)

Abstract

γ-Aminobutyric acid type C (GABA(C)) receptors identified in retina appear to be composed of GABA ρ sub-units. The purpose of this study was to localize signals for homooligomeric assembly of ρ1 subunits and to investigate whether the same region contained signals for heterooligomeric interaction with ρ1 subunits. In vitro translated human ρ1 was shown to be membrane-associated, and proteinase K susceptibility studies indicated that the N terminus was oriented in the lumen of ER-derived microsomal vesicles. This orientation suggested the involvement of the N terminus of ρ1 in the initial steps of subunit assembly. To test this hypothesis, mutants were created containing only N-terminal sequences (N-ρ1) or C-terminal sequences (C-ρ1) of ρ1. Coimmunoprecipitation studies revealed that N-ρ1, but not C- ρ1, interacted with ρ1 in vitro. When coexpressed in Xenopus oocytes, N- ρ1 interfered with ρ1 receptor formation. Together, these data suggested that signals for ρ1 homooligomeric assembly reside in the N-terminal half of the subunit. Sequential immunoprecipitations were then performed upon cotranslated ρ1 and ρ2 sub-units which demonstrated that ρ1 and ρ2 interacted in vitro. Co-immunoprecipitation indicated that N-ρ1 specifically associated with ρ2. Therefore, the N-terminal regions of p subunits contain the initial signals for both homooligomeric and heterooligomeric assembly into receptors with GABA(C) properties.

Original languageEnglish
Pages (from-to)13750-13757
Number of pages8
JournalJournal of Biological Chemistry
Volume272
Issue number21
DOIs
StatePublished - May 23 1997
Externally publishedYes

Fingerprint

GABA Receptors
Immunoprecipitation
gamma-Aminobutyric Acid
Aminobutyrates
Endopeptidase K
Xenopus
Oocytes
Retina
Membranes
In Vitro Techniques
GABA-C receptor

ASJC Scopus subject areas

  • Biochemistry

Cite this

The N-terminal domain of human GABA receptor ρ1 subunits contains signals for homooligomeric and heterooligomeric interaction. / Hackam, Abigail S; Wang, Tian Li; Guggino, William B.; Cutting, Garry R.

In: Journal of Biological Chemistry, Vol. 272, No. 21, 23.05.1997, p. 13750-13757.

Research output: Contribution to journalArticle

@article{4084c7db995241baa2439b1e6c956e18,
title = "The N-terminal domain of human GABA receptor ρ1 subunits contains signals for homooligomeric and heterooligomeric interaction",
abstract = "γ-Aminobutyric acid type C (GABA(C)) receptors identified in retina appear to be composed of GABA ρ sub-units. The purpose of this study was to localize signals for homooligomeric assembly of ρ1 subunits and to investigate whether the same region contained signals for heterooligomeric interaction with ρ1 subunits. In vitro translated human ρ1 was shown to be membrane-associated, and proteinase K susceptibility studies indicated that the N terminus was oriented in the lumen of ER-derived microsomal vesicles. This orientation suggested the involvement of the N terminus of ρ1 in the initial steps of subunit assembly. To test this hypothesis, mutants were created containing only N-terminal sequences (N-ρ1) or C-terminal sequences (C-ρ1) of ρ1. Coimmunoprecipitation studies revealed that N-ρ1, but not C- ρ1, interacted with ρ1 in vitro. When coexpressed in Xenopus oocytes, N- ρ1 interfered with ρ1 receptor formation. Together, these data suggested that signals for ρ1 homooligomeric assembly reside in the N-terminal half of the subunit. Sequential immunoprecipitations were then performed upon cotranslated ρ1 and ρ2 sub-units which demonstrated that ρ1 and ρ2 interacted in vitro. Co-immunoprecipitation indicated that N-ρ1 specifically associated with ρ2. Therefore, the N-terminal regions of p subunits contain the initial signals for both homooligomeric and heterooligomeric assembly into receptors with GABA(C) properties.",
author = "Hackam, {Abigail S} and Wang, {Tian Li} and Guggino, {William B.} and Cutting, {Garry R.}",
year = "1997",
month = "5",
day = "23",
doi = "10.1074/jbc.272.21.13750",
language = "English",
volume = "272",
pages = "13750--13757",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "21",

}

TY - JOUR

T1 - The N-terminal domain of human GABA receptor ρ1 subunits contains signals for homooligomeric and heterooligomeric interaction

AU - Hackam, Abigail S

AU - Wang, Tian Li

AU - Guggino, William B.

AU - Cutting, Garry R.

PY - 1997/5/23

Y1 - 1997/5/23

N2 - γ-Aminobutyric acid type C (GABA(C)) receptors identified in retina appear to be composed of GABA ρ sub-units. The purpose of this study was to localize signals for homooligomeric assembly of ρ1 subunits and to investigate whether the same region contained signals for heterooligomeric interaction with ρ1 subunits. In vitro translated human ρ1 was shown to be membrane-associated, and proteinase K susceptibility studies indicated that the N terminus was oriented in the lumen of ER-derived microsomal vesicles. This orientation suggested the involvement of the N terminus of ρ1 in the initial steps of subunit assembly. To test this hypothesis, mutants were created containing only N-terminal sequences (N-ρ1) or C-terminal sequences (C-ρ1) of ρ1. Coimmunoprecipitation studies revealed that N-ρ1, but not C- ρ1, interacted with ρ1 in vitro. When coexpressed in Xenopus oocytes, N- ρ1 interfered with ρ1 receptor formation. Together, these data suggested that signals for ρ1 homooligomeric assembly reside in the N-terminal half of the subunit. Sequential immunoprecipitations were then performed upon cotranslated ρ1 and ρ2 sub-units which demonstrated that ρ1 and ρ2 interacted in vitro. Co-immunoprecipitation indicated that N-ρ1 specifically associated with ρ2. Therefore, the N-terminal regions of p subunits contain the initial signals for both homooligomeric and heterooligomeric assembly into receptors with GABA(C) properties.

AB - γ-Aminobutyric acid type C (GABA(C)) receptors identified in retina appear to be composed of GABA ρ sub-units. The purpose of this study was to localize signals for homooligomeric assembly of ρ1 subunits and to investigate whether the same region contained signals for heterooligomeric interaction with ρ1 subunits. In vitro translated human ρ1 was shown to be membrane-associated, and proteinase K susceptibility studies indicated that the N terminus was oriented in the lumen of ER-derived microsomal vesicles. This orientation suggested the involvement of the N terminus of ρ1 in the initial steps of subunit assembly. To test this hypothesis, mutants were created containing only N-terminal sequences (N-ρ1) or C-terminal sequences (C-ρ1) of ρ1. Coimmunoprecipitation studies revealed that N-ρ1, but not C- ρ1, interacted with ρ1 in vitro. When coexpressed in Xenopus oocytes, N- ρ1 interfered with ρ1 receptor formation. Together, these data suggested that signals for ρ1 homooligomeric assembly reside in the N-terminal half of the subunit. Sequential immunoprecipitations were then performed upon cotranslated ρ1 and ρ2 sub-units which demonstrated that ρ1 and ρ2 interacted in vitro. Co-immunoprecipitation indicated that N-ρ1 specifically associated with ρ2. Therefore, the N-terminal regions of p subunits contain the initial signals for both homooligomeric and heterooligomeric assembly into receptors with GABA(C) properties.

UR - http://www.scopus.com/inward/record.url?scp=0030985231&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030985231&partnerID=8YFLogxK

U2 - 10.1074/jbc.272.21.13750

DO - 10.1074/jbc.272.21.13750

M3 - Article

C2 - 9153229

AN - SCOPUS:0030985231

VL - 272

SP - 13750

EP - 13757

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 21

ER -