Limits...
A 64 kDa sucrose binding protein is membrane-associated and tonoplast-localized in developing mung bean seeds.

Wang J, Suen PK, Xu ZF, Jiang L - J. Exp. Bot. (2009)

Bottom Line: Immunogold electron microscope (EM) studies on ultra-thin sections of high-pressure freezing/frozen substituted developing mung bean cotyledons demonstrated that VrSBP1 was localized specifically to the tonoplast of the protein storage vacuole and to the limiting membrane of a novel putative prevacuolar compartment.Biochemical and subcellular fractionation studies further demonstrated that VrSBP1 proteins were membrane-associated in developing mung beans, consistent with their tonoplast localization.This study thus shows convincing evidence of tonoplast-localization of a plant SBP for its future functional characterization and provides a model of studying non-integral membrane proteins associated with the tonoplasts in plant cells.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology and Centre for Cell and Development Biology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.

ABSTRACT
Sucrose binding proteins (SBPs) were predicted to be membrane-associated, but have been shown to localize in the lumen of protein storage vacuoles of various seeds. In this study, a new 64 kDa SBP has been identified from developing mung bean (Vigna radiata) seeds (here termed VrSBP1) via MS/MS analysis and N-terminal amino acid sequencing analysis and specific antibodies were generated using purified VrSBP1 proteins. Western blot analysis with the new VrSBP1 antibodies showed that, similar to most seed storage proteins, VrSBP1 proteins accumulated during seed development and were subsequently mobilized once the mung bean seeds germinated. Immunogold electron microscope (EM) studies on ultra-thin sections of high-pressure freezing/frozen substituted developing mung bean cotyledons demonstrated that VrSBP1 was localized specifically to the tonoplast of the protein storage vacuole and to the limiting membrane of a novel putative prevacuolar compartment. Biochemical and subcellular fractionation studies further demonstrated that VrSBP1 proteins were membrane-associated in developing mung beans, consistent with their tonoplast localization. This study thus shows convincing evidence of tonoplast-localization of a plant SBP for its future functional characterization and provides a model of studying non-integral membrane proteins associated with the tonoplasts in plant cells.

Show MeSH

Related in: MedlinePlus

VrSBP1 proteins are present in mung bean seedlings. Both soluble proteins (CS) and membrane proteins (CM) were first isolated from various tissues of mung bean seedlings including stems, unifoliate, new trifoliate, and young trifoliate leaves, followed by protein separation via SDS-PAGE and Western blot analysis using VrSBP1 antibodies. An asterisk indicates the position of the VrSBP1.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC2651462&req=5

fig10: VrSBP1 proteins are present in mung bean seedlings. Both soluble proteins (CS) and membrane proteins (CM) were first isolated from various tissues of mung bean seedlings including stems, unifoliate, new trifoliate, and young trifoliate leaves, followed by protein separation via SDS-PAGE and Western blot analysis using VrSBP1 antibodies. An asterisk indicates the position of the VrSBP1.

Mentions: To find out if VrSBP1 proteins were also present in other tissues of mung bean, Western blot analysis was also performed with VrSBP1 antibodies on proteins isolated from various tissues of mung bean seedlings. Both soluble proteins (CS) and membrane proteins (CM) were first isolated from various tissues of mung bean seedlings including stems, unifoliate, new trifoliate, and young trifoliate leaves, followed by protein separation via SDS-PAGE and Western blot analysis using VrSBP1 antibodies. As shown in Fig. 10, similar amounts of VrSBP1 proteins were detected in the CM fractions of stem, new trifoliate, and young trifoliate leaves (Fig. 10, lanes 2, 6, 8), but little VrSBP1 was present in unifoliate leaves (Fig. 10, lane 4). These results indicated that, in addition to developing seeds, the presence of VrSBP1 in mung bean seedlings might also suggest its roles in these tissues. In addition, the presence of VrSBP1 in the CM fraction rather than in the CS fraction in the seedlings is also consistent with its nature of membrane association.


A 64 kDa sucrose binding protein is membrane-associated and tonoplast-localized in developing mung bean seeds.

Wang J, Suen PK, Xu ZF, Jiang L - J. Exp. Bot. (2009)

VrSBP1 proteins are present in mung bean seedlings. Both soluble proteins (CS) and membrane proteins (CM) were first isolated from various tissues of mung bean seedlings including stems, unifoliate, new trifoliate, and young trifoliate leaves, followed by protein separation via SDS-PAGE and Western blot analysis using VrSBP1 antibodies. An asterisk indicates the position of the VrSBP1.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC2651462&req=5

fig10: VrSBP1 proteins are present in mung bean seedlings. Both soluble proteins (CS) and membrane proteins (CM) were first isolated from various tissues of mung bean seedlings including stems, unifoliate, new trifoliate, and young trifoliate leaves, followed by protein separation via SDS-PAGE and Western blot analysis using VrSBP1 antibodies. An asterisk indicates the position of the VrSBP1.
Mentions: To find out if VrSBP1 proteins were also present in other tissues of mung bean, Western blot analysis was also performed with VrSBP1 antibodies on proteins isolated from various tissues of mung bean seedlings. Both soluble proteins (CS) and membrane proteins (CM) were first isolated from various tissues of mung bean seedlings including stems, unifoliate, new trifoliate, and young trifoliate leaves, followed by protein separation via SDS-PAGE and Western blot analysis using VrSBP1 antibodies. As shown in Fig. 10, similar amounts of VrSBP1 proteins were detected in the CM fractions of stem, new trifoliate, and young trifoliate leaves (Fig. 10, lanes 2, 6, 8), but little VrSBP1 was present in unifoliate leaves (Fig. 10, lane 4). These results indicated that, in addition to developing seeds, the presence of VrSBP1 in mung bean seedlings might also suggest its roles in these tissues. In addition, the presence of VrSBP1 in the CM fraction rather than in the CS fraction in the seedlings is also consistent with its nature of membrane association.

Bottom Line: Immunogold electron microscope (EM) studies on ultra-thin sections of high-pressure freezing/frozen substituted developing mung bean cotyledons demonstrated that VrSBP1 was localized specifically to the tonoplast of the protein storage vacuole and to the limiting membrane of a novel putative prevacuolar compartment.Biochemical and subcellular fractionation studies further demonstrated that VrSBP1 proteins were membrane-associated in developing mung beans, consistent with their tonoplast localization.This study thus shows convincing evidence of tonoplast-localization of a plant SBP for its future functional characterization and provides a model of studying non-integral membrane proteins associated with the tonoplasts in plant cells.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology and Centre for Cell and Development Biology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.

ABSTRACT
Sucrose binding proteins (SBPs) were predicted to be membrane-associated, but have been shown to localize in the lumen of protein storage vacuoles of various seeds. In this study, a new 64 kDa SBP has been identified from developing mung bean (Vigna radiata) seeds (here termed VrSBP1) via MS/MS analysis and N-terminal amino acid sequencing analysis and specific antibodies were generated using purified VrSBP1 proteins. Western blot analysis with the new VrSBP1 antibodies showed that, similar to most seed storage proteins, VrSBP1 proteins accumulated during seed development and were subsequently mobilized once the mung bean seeds germinated. Immunogold electron microscope (EM) studies on ultra-thin sections of high-pressure freezing/frozen substituted developing mung bean cotyledons demonstrated that VrSBP1 was localized specifically to the tonoplast of the protein storage vacuole and to the limiting membrane of a novel putative prevacuolar compartment. Biochemical and subcellular fractionation studies further demonstrated that VrSBP1 proteins were membrane-associated in developing mung beans, consistent with their tonoplast localization. This study thus shows convincing evidence of tonoplast-localization of a plant SBP for its future functional characterization and provides a model of studying non-integral membrane proteins associated with the tonoplasts in plant cells.

Show MeSH
Related in: MedlinePlus