Calmodulin is involved in the dual subcellular location of two chloroplast proteins

Cell compartmentalization is an essential process by which eukaryotic cells separate and control biological processes. Although calmodulins are well-known to regulate catalytic properties of their targets, we show here their involvement in the subcellular location of two plant proteins. Both proteins exhibit a dual location, namely in the cytosol in addition to their association to plastids (where they are known to fulfil their role). One of these proteins, ceQORH, a long-chain fatty acid reductase, was analyzed in more detail, and its calmodulin-binding site was identified by specific mutations. Such a mutated form is predominantly targeted to plastids at the expense of its cytosolic location. The second protein, TIC32, was also shown to be dependent on its calmodulin-binding site for retention in the cytosol. Complementary approaches (bimolecular fluorescence complementation and reverse genetics) demonstrated that the calmodulin isoform CAM5 is specifically involved in the retention of ceQORH in the cytosol. This study identifies a new role for calmodulin and sheds new light on the intriguing CaM-binding properties of hundreds of plastid proteins, despite the fact that no CaM or CaM-like proteins were identified in plastids.

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Characterization of ATP and calmodulin-binding properties of a truncated form of Bacillus anthracis adenylate cyclase

Biochemistry ◽

10.1021/bi00472a024 ◽

1990 ◽

Vol 29 (20) ◽

pp. 4922-4928 ◽

Cited By ~ 31

Author(s):

Elisabeth Labruyere ◽

Michele Mock ◽

Daniel Ladant ◽

Susan Michelson ◽

Anne Marie Gilles ◽

...

Keyword(s):

Adenylate Cyclase ◽

Bacillus Anthracis ◽

Truncated Form ◽

Binding Properties ◽

Calmodulin Binding

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Characterization of the Calmodulin-binding Site of Nonerythroid α-Spectrin

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)83624-9 ◽

1989 ◽

Vol 264 (10) ◽

pp. 5826-5830 ◽

Cited By ~ 4

Author(s):

T L Leto ◽

S Pleasic ◽

B G Forget ◽

E J Benz ◽

V T Marchesi

Keyword(s):

Binding Site ◽

Calmodulin Binding

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Mechanisms Applied by Protein Inhibitors to Inhibit Cysteine Proteases

International Journal of Molecular Sciences ◽

10.3390/ijms22030997 ◽

2021 ◽

Vol 22 (3) ◽

pp. 997

Author(s):

Livija Tušar ◽

Aleksandra Usenik ◽

Boris Turk ◽

Dušan Turk

Keyword(s):

Binding Site ◽

Structural Information ◽

General Rule ◽

Structural Data ◽

Cysteine Proteases ◽

Protein Inhibitors ◽

Active Site Cleft ◽

Living Organisms ◽

And Control ◽

Binding Mechanisms

Protein inhibitors of proteases are an important tool of nature to regulate and control proteolysis in living organisms under physiological and pathological conditions. In this review, we analyzed the mechanisms of inhibition of cysteine proteases on the basis of structural information and compiled kinetic data. The gathered structural data indicate that the protein fold is not a major obstacle for the evolution of a protease inhibitor. It appears that nature can convert almost any starting fold into an inhibitor of a protease. In addition, there appears to be no general rule governing the inhibitory mechanism. The structural data make it clear that the “lock and key” mechanism is a historical concept with limited validity. However, the analysis suggests that the shape of the active site cleft of proteases imposes some restraints. When the S1 binding site is shaped as a pocket buried in the structure of protease, inhibitors can apply substrate-like binding mechanisms. In contrast, when the S1 binding site is in part exposed to solvent, the substrate-like inhibition cannot be employed. It appears that all proteases, with the exception of papain-like proteases, belong to the first group of proteases. Finally, we show a number of examples and provide hints on how to engineer protein inhibitors.

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A yeast protein possesses the DNA-binding properties of the adenovirus major late transcription factor.

Molecular and Cellular Biology ◽

10.1128/mcb.9.2.820 ◽

1989 ◽

Vol 9 (2) ◽

pp. 820-822 ◽

Cited By ~ 5

Author(s):

L A Chodosh ◽

S Buratowski ◽

P A Sharp

Keyword(s):

Transcription Factor ◽

Dna Binding ◽

Binding Site ◽

Upstream Stimulatory Factor ◽

Binding Properties ◽

Yeast Saccharomyces Cerevisiae ◽

Human Promoter ◽

Late Transcription ◽

Stimulatory Factor ◽

Dna Binding Properties

The adenovirus major late transcription factor (MLTF), or upstream stimulatory factor, is a human promoter-specific transcription factor which recognizes the near-palindromic sequence GGCCACGTGACC (R. W. Carthew, L. A. Chodosh, and P. A. Sharp, Cell 43:439-448, 1985; L. A. Chodosh, R. W. Carthew, and P. A. Sharp, Mol. Cell. Biol. 6:4723-4733, 1986; M. Sawadogo and R. G. Roeder, Cell 43:165-175, 1985). We describe here a protein found in the yeast Saccharomyces cerevisiae which possesses DNA-binding properties that are virtually identical to those of human MLTF. These two proteins recognize the same DNA-binding site, make the same purine nucleotide contacts, and are affected in the same manner by mutations in the MLTF-binding site.

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A Ca2+-Binding Domain in RyR1 that Interacts with the Calmodulin Binding Site and Modulates Channel Activity

Biophysical Journal ◽

10.1529/biophysj.105.066092 ◽

2006 ◽

Vol 90 (1) ◽

pp. 173-182 ◽

Cited By ~ 44

Author(s):

Liangwen Xiong ◽

Jia-Zheng Zhang ◽

Rong He ◽

Susan L. Hamilton

Keyword(s):

Binding Site ◽

Binding Domain ◽

Channel Activity ◽

Calmodulin Binding

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Characterization of the stilbenedisulphonate binding site on band 3 Memphis variant II (Pro-854→Leu)

Biochemical Journal ◽

10.1042/bj3170509 ◽

1996 ◽

Vol 317 (2) ◽

pp. 509-514 ◽

Cited By ~ 6

Author(s):

James M. SALHANY ◽

Renee L. SLOAN ◽

Lawrence M. SCHOPFER

Keyword(s):

Binding Site ◽

Conformational Changes ◽

Covalent Binding ◽

Band 3 ◽

Blood Group Antigen ◽

Cross Linking ◽

Anion Exchange Protein ◽

Membrane Bound ◽

And Control

Band 3 Memphis variant II is a mutant anion-exchange protein associated with the Diego a+ blood group antigen. There are two mutations in this transporter: Lys-56 → Glu within the cytoplasmic domain, and Pro-854 → Leu within the membrane-bound domain. The Pro-854 mutation, which is thought to give rise to the antigenicity, is located within the C-terminal subdomain of the membrane-bound domain. Yet, there is an apparent enhancement in the rate of covalent binding of H2DIDS (4,4´-di-isothiocyanatodihydro-2,2´-stilbenedisulphonate) to ‘lysine A’ (Lys-539) in the N-terminal subdomain, suggesting widespread conformational changes. In this report, we have used various kinetic assays which differentiate between conformational changes in the two subdomains, to characterize the stilbenedisulphonate site on band 3 Memphis variant II. We have found a significantly higher H2DIDS (a C-terminal-sensitive inhibitor) affinity for band 3 Memphis variant II, due to a lower H2DIDS ‘off’ rate constant, but no difference was found between mutant and control when DBDS (4,4´-dibenzamido-2,2´-stilbenedisulphonate) (a C-terminal-insensitive inhibitor) ‘off’ rates were measured. Furthermore, there were no differences in the rates of covalent binding to lysine A, for either DIDS (4,4´-di-isothiocyanato-2,2´-stilbenedisulphonate) or H2DIDS. However, the rate of covalent intrasubunit cross-linking of Lys-539 and Lys-851 by H2DIDS was abnormally low for band 3 Memphis variant II. These results suggest that the Pro-854 → Leu mutation causes a localized conformational change in the C-terminal subdomain of band 3.

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A role for glutamate decarboxylase during tomato ripening: the characterisation of a cDNA encoding a putative glutamate decarboxylase with a calmodulin-binding site

Plant Molecular Biology ◽

10.1007/bf00020887 ◽

1995 ◽

Vol 27 (6) ◽

pp. 1143-1151 ◽

Cited By ~ 39

Author(s):

Pedro P. Gallego ◽

Lee Whotton ◽

Steve Picton ◽

Don Grierson ◽

Julie E. Gray

Keyword(s):

Binding Site ◽

Glutamate Decarboxylase ◽

Calmodulin Binding

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The essential mitotic target of calmodulin is the 110-kilodalton component of the spindle pole body in Saccharomyces cerevisiae

Molecular and Cellular Biology ◽

10.1128/mcb.13.12.7913-7924.1993 ◽

1993 ◽

Vol 13 (12) ◽

pp. 7913-7924

Author(s):

J R Geiser ◽

H A Sundberg ◽

B H Chang ◽

E G Muller ◽

T N Davis

Keyword(s):

Amino Acid ◽

Sequence Analysis ◽

Binding Site ◽

Hybrid System ◽

Spindle Pole Body ◽

Spindle Pole ◽

Amino Acid Residues ◽

Calmodulin Binding ◽

Pole Body ◽

Two Hybrid

Two independent methods identified the spindle pole body component Nuf1p/Spc110p as the essential mitotic target of calmodulin. Extragenic suppressors of cmd1-1 were isolated and found to define three loci, XCM1, XCM2, and XCM3 (extragenic suppressor of cmd1-1). The gene encoding a dominant suppressor allele of XCM1 was cloned. On the basis of DNA sequence analysis, genetic cosegregation, and mutational analysis, XCM1 was identified as NUF1/SPC110. Independently, a C-terminal portion of Nuf1p/Spc110p, amino acid residues 828 to 944, was isolated as a calmodulin-binding protein by the two-hybrid system. As assayed by the two-hybrid system, Nuf1p/Spc110p interacts with wild-type calmodulin and triple-mutant calmodulins defective in binding Ca2+ but not with two mutant calmodulins that confer a temperature-sensitive phenotype. Deletion analysis by the two-hybrid system mapped the calmodulin-binding site of Nuf1p/Spc110p to amino acid residues 900 to 927. Direct binding between calmodulin and Nuf1p/Spc110p was demonstrated by a modified gel overlay assay. Furthermore, indirect immunofluorescence with fixation procedures known to aid visualization of spindle pole body components localized calmodulin to the spindle pole body. Sequence analysis of five suppressor alleles of NUF1/SPC110 indicated that suppression of cmd1-1 occurs by C-terminal truncation of Nuf1p/Spc110p at amino acid residues 856, 863, or 881, thereby removing the calmodulin-binding site.

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Exploring the binding properties of agonists interacting with human TGR5 using structural modeling, molecular docking and dynamics simulations

RSC Advances ◽

10.1039/c4ra16617e ◽

2015 ◽

Vol 5 (19) ◽

pp. 14202-14213 ◽

Cited By ~ 17

Author(s):

Thangaraj Sindhu ◽

Pappu Srinivasan

Keyword(s):

Molecular Docking ◽

Binding Site ◽

Type Ii Diabetes ◽

Computational Study ◽

Structural Modeling ◽

Type Ii ◽

Binding Properties ◽

Pharmacological Target ◽

Dynamics Simulations ◽

Molecular Docking And Dynamics

TGR5, act as a potential pharmacological target in the treatment of type II diabetes. In the computational study, structural modeling and binding site prediction of TGR5 receptor was performed. Two well-known agonists of TGR5 used to investigate the mode and mechanism of binding.

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