PMID- 10449730
OWN - NLM
STAT- MEDLINE
DCOM- 19990909
LR  - 20190501
IS  - 0027-8424 (Print)
IS  - 0027-8424 (Linking)
VI  - 96
IP  - 17
DP  - 1999 Aug 17
TI  - Regions on adenylyl cyclase that are necessary for inhibition of activity by beta
      gamma and G(ialpha) subunits of heterotrimeric G proteins.
PG  - 9551-6
AB  - The two large cytoplasmic domains (C1 and C2) of adenylyl cyclases (AC), when
      expressed separately and mixed together, reconstitute enzyme activity that can be
      regulated by various modulators. Therefore, we have used the C1 or its C1a
      subdomain and C2 regions from type I AC (ACI) and type V AC (ACV) to identify the
      region on ACI that interacts with beta gamma subunits of heterotrimeric G
      proteins. In addition, we also used a chimeric C1 domain (VC1aIC1b) in which the 
      C1a region was derived from ACV and the C1b region was from ACI. By mixing the C1
      or C1a or VC1aIC1b domains with C2 regions of ACI or ACV, we have shown that the 
      C1a region (amino acids 236-471) of ACI is sufficient to observe beta
      gamma-mediated inhibition of enzyme activity, which is stimulated by either
      constitutively active G(salpha) (G(salpha)*) or Ca(2+)/calmodulin (CaM). Although
      the C1b region and C2 domain of ACI were by themselves not sufficient for
      inhibition of activity by beta gamma subunits, the presence of both of these
      regions formed another beta gamma interaction site that was sufficient to observe
      G(salpha)*- or Ca(2+)/CaM-stimulated activity. Inhibition of AC activity
      attributable to interaction of beta gamma subunits at either of the two sites was
      blocked by a peptide (QEHA) that has previously been shown to inhibit the effects
      of beta gamma on various effectors. Moreover, the C1 region of ACI was sufficient
      to observe G(ialpha1)-elicited inhibition of Ca(2+)/CaM-stimulated activity.
      Although the C1a region of ACV was sufficient for inhibition of activity by
      G(ialpha1), the presence of C1b region from either ACI or ACV increased
      sensitivity to inhibition by the inhibitory G protein. Thus, the inhibitory
      influences of G(ialpha1) are mediated on the C1 regions of both ACI and ACV. The 
      effects of beta gamma on ACI can be mediated by interactions with the C1a region 
      and a beta gamma interacting site formed by the C1b and C2 domains of this
      enzyme.
FAU - Wittpoth, C
AU  - Wittpoth C
AD  - Department of Pharmacology, University of Tennessee, The Health Science Center,
      874 Union Avenue, Memphis, TN 38163, USA.
FAU - Scholich, K
AU  - Scholich K
FAU - Yigzaw, Y
AU  - Yigzaw Y
FAU - Stringfield, T M
AU  - Stringfield TM
FAU - Patel, T B
AU  - Patel TB
LA  - eng
GR  - R01 HL059679/HL/NHLBI NIH HHS/United States
GR  - HL 59679/HL/NHLBI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Proc Natl Acad Sci U S A
JT  - Proceedings of the National Academy of Sciences of the United States of America
JID - 7505876
RN  - 0 (Calmodulin)
RN  - 0 (G-protein Beta gamma)
RN  - 0 (GTP-Binding Protein beta Subunits)
RN  - 0 (GTP-Binding Protein gamma Subunits)
RN  - 0 (Recombinant Proteins)
RN  - EC 3.6.1.- (GTP-Binding Proteins)
RN  - EC 3.6.5.1 (GTP-Binding Protein alpha Subunits, Gi-Go)
RN  - EC 3.6.5.1 (Heterotrimeric GTP-Binding Proteins)
RN  - EC 4.6.1.1 (Adenylyl Cyclases)
SB  - IM
MH  - Adenylyl Cyclases/*metabolism
MH  - Calmodulin/metabolism
MH  - Escherichia coli
MH  - GTP-Binding Protein alpha Subunits, Gi-Go/*metabolism
MH  - *GTP-Binding Protein beta Subunits
MH  - *GTP-Binding Protein gamma Subunits
MH  - GTP-Binding Proteins/*metabolism
MH  - *Heterotrimeric GTP-Binding Proteins
MH  - Protein Conformation
MH  - Recombinant Proteins/metabolism
MH  - Structure-Activity Relationship
PMC - PMC22246
EDAT- 1999/08/18 00:00
MHDA- 1999/08/18 00:01
CRDT- 1999/08/18 00:00
PHST- 1999/08/18 00:00 [pubmed]
PHST- 1999/08/18 00:01 [medline]
PHST- 1999/08/18 00:00 [entrez]
AID - 10.1073/pnas.96.17.9551 [doi]
PST - ppublish
SO  - Proc Natl Acad Sci U S A. 1999 Aug 17;96(17):9551-6. doi:
      10.1073/pnas.96.17.9551.