Regulatory role of the N-terminus of the vacuolar calcium-ATPase in Cauliflower
(2000) In Plant Physiology 122(2). p.517-526- Abstract
- The vacuolar calmodulin (CaM)-stimulated Ca(2+)-ATPase, BCA1p, in cauliflower (Brassica oleracea) has an extended N terminus, which was suggested to contain a CaM-binding domain (S. Malmström, P. Askerlund, M.G. Palmgren [1997] FEBS Lett 400: 324-328). The goal of the present study was to determine the role of the N terminus in regulating BCA1p. Western analysis using three different antisera showed that the N terminus of BCA1p is cleaved off by trypsin and that the N terminus contains the CaM-binding domain. Furthermore, the expressed N terminus binds CaM in a Ca(2+)-dependent manner. A synthetic peptide corresponding to the CaM-binding domain of BCA1p (Ala-19 to Leu-43) strongly inhibited ATP-dependent Ca(2+) pumping by BCA1p in... (More)
- The vacuolar calmodulin (CaM)-stimulated Ca(2+)-ATPase, BCA1p, in cauliflower (Brassica oleracea) has an extended N terminus, which was suggested to contain a CaM-binding domain (S. Malmström, P. Askerlund, M.G. Palmgren [1997] FEBS Lett 400: 324-328). The goal of the present study was to determine the role of the N terminus in regulating BCA1p. Western analysis using three different antisera showed that the N terminus of BCA1p is cleaved off by trypsin and that the N terminus contains the CaM-binding domain. Furthermore, the expressed N terminus binds CaM in a Ca(2+)-dependent manner. A synthetic peptide corresponding to the CaM-binding domain of BCA1p (Ala-19 to Leu-43) strongly inhibited ATP-dependent Ca(2+) pumping by BCA1p in cauliflower low-density membranes, indicating that the CaM-binding region of BCA1p also has an autoinhibitory function. The expressed N terminus of BCA1p and a synthetic peptide (Ala-19 to Met-39) were good substrates for phosphorylation by protein kinase C. Sequencing of the phosphorylated fusion protein and peptide suggested serine-16 and/or serine-28 as likely targets for phosphorylation. Phosphorylation of serine-28 had no effect on CaM binding to the alanine-19 to methionine-39 peptide. Our results demonstrate the regulatory importance of the N terminus of BCA1p as a target for CaM binding, trypsin cleavage, and phosphorylation, as well as its importance as an autoinhibitory domain. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1474798
- author
- Malmström, Susanna ; Åkerlund, Hans-Erik LU and Askerlund, Per
- organization
- publishing date
- 2000
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Plant Physiology
- volume
- 122
- issue
- 2
- pages
- 517 - 526
- publisher
- American Society of Plant Biologists
- external identifiers
-
- scopus:0034144402
- ISSN
- 1532-2548
- DOI
- 10.1104/pp.122.2.517
- language
- English
- LU publication?
- yes
- id
- f691bca8-e0d3-46a6-94d6-8ca12f9c12b1 (old id 1474798)
- date added to LUP
- 2016-04-04 07:48:51
- date last changed
- 2022-01-29 02:38:13
@article{f691bca8-e0d3-46a6-94d6-8ca12f9c12b1,
abstract = {{The vacuolar calmodulin (CaM)-stimulated Ca(2+)-ATPase, BCA1p, in cauliflower (Brassica oleracea) has an extended N terminus, which was suggested to contain a CaM-binding domain (S. Malmström, P. Askerlund, M.G. Palmgren [1997] FEBS Lett 400: 324-328). The goal of the present study was to determine the role of the N terminus in regulating BCA1p. Western analysis using three different antisera showed that the N terminus of BCA1p is cleaved off by trypsin and that the N terminus contains the CaM-binding domain. Furthermore, the expressed N terminus binds CaM in a Ca(2+)-dependent manner. A synthetic peptide corresponding to the CaM-binding domain of BCA1p (Ala-19 to Leu-43) strongly inhibited ATP-dependent Ca(2+) pumping by BCA1p in cauliflower low-density membranes, indicating that the CaM-binding region of BCA1p also has an autoinhibitory function. The expressed N terminus of BCA1p and a synthetic peptide (Ala-19 to Met-39) were good substrates for phosphorylation by protein kinase C. Sequencing of the phosphorylated fusion protein and peptide suggested serine-16 and/or serine-28 as likely targets for phosphorylation. Phosphorylation of serine-28 had no effect on CaM binding to the alanine-19 to methionine-39 peptide. Our results demonstrate the regulatory importance of the N terminus of BCA1p as a target for CaM binding, trypsin cleavage, and phosphorylation, as well as its importance as an autoinhibitory domain.}},
author = {{Malmström, Susanna and Åkerlund, Hans-Erik and Askerlund, Per}},
issn = {{1532-2548}},
language = {{eng}},
number = {{2}},
pages = {{517--526}},
publisher = {{American Society of Plant Biologists}},
series = {{Plant Physiology}},
title = {{Regulatory role of the N-terminus of the vacuolar calcium-ATPase in Cauliflower}},
url = {{http://dx.doi.org/10.1104/pp.122.2.517}},
doi = {{10.1104/pp.122.2.517}},
volume = {{122}},
year = {{2000}},
}