See the published version of this article at BMC Plant Biology.
This is a preprint, a preliminary version of a manuscript that has not completed peer review at a journal. Research Square does not conduct peer review prior to posting preprints. The posting of a preprint on this server should not be interpreted as an endorsement of its validity or suitability for dissemination as established information or for guiding clinical practice.
Learn more about In Review
Research article
Characterization of a vacuolar sucrose transporter, HbSUT5, from Hevea brasiliensis: involvement in latex production through regulation of intracellular sucrose transport in the bark and laticifers
xiangyu long
Chinese Academy of Medical Sciences and Peking Union Medical College Hospital and Institute of Dermatology
Corresponding Author
License:
This work is licensed under a CC BY 4.0 License. Read Full License
View the published version at BMC Plant Biology.
Background: Sucrose (Suc), as the precursor molecule for rubber biosynthesis in Hevea brasiliensis , is transported via phloem-mediated long-distance transport from leaves to laticifers in trunk bark, where latex (cytoplasm of laticifers) is tapped for rubber. In our previous report, six Suc transporter (SUT) genes have been cloned in Hevea tree, among which HbSUT3 is verified to play an active role in Suc loading to the laticifers. In this study, another latex-abundant SUT isoform, HbSUT5 , with expressions only inferior to HbSUT3 was characterized especially for its roles in latex production. Results: Both phylogenetic analysis and subcellular localization identify HbSUT5 as a tonoplast-localized SUT protein under the SUT4-clade (=type III). Suc uptake assay in baker’s yeast reveals HbSUT5 to be a typical Suc-H + symporter, but its high affinity for Suc (Km = 2.03 mM at pH 5.5) and the similar efficiency in transporting both Suc and maltose making it a peculiar SUT under the SUT4-clade. At the transcript level, HbSUT5 is abundantly and preferentially expressed in Hevea barks. The transcripts of HbSUT5 are conspicuously decreased both in Hevea latex and bark by two yield-stimulating treatments of tapping and ethephon, the patterns of which are contrary to HbSUT3. Under the ethephon treatment, the Suc level in latex cytosol decreases significantly, but that in latex lutoids (polydispersed vacuoles) changes little, suggesting a role of the decreased HbSUT5 expression in Suc compartmentalization in the lutoids and thus enhancing the Suc sink strength in laticifers. Conclusions: Our findings provide insights into the roles of a vacuolar sucrose transporter, HbSUT5, in Suc exchange between lutoids and cytosol in rubber-producing laticifers.
Keywords
Sucrose transporter, Laticifer, Vacuole, Latex production, Rubber tree
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
This is a list of supplementary files associated with this preprint. Click to download.
Badges
Prescreen
This manuscript passed our Prescreen assessment
Complete author information
Appropriate declaration statements
Potential risks to human health
Prescreen
Peer Review Timeline
CURRENT STATUS: Published
Version 3
Posted 03 Jan, 2020
Published
On 27 Dec, 2019
No community comments so far
Editorial decision: Accept
On 18 Dec, 2019
Editor assigned
On 17 Dec, 2019
Submission checks complete
On 16 Dec, 2019
Editor invited
On 16 Dec, 2019
No comments provided
Editorial decision: Minor revision
On 16 Dec, 2019
Reviewer #1 agreed
On 22 Oct, 2019
Reviewers invited
Invitations sent on 21 Oct, 2019
Editor assigned
On 20 Oct, 2019
Submission checks complete
On 19 Oct, 2019
Editor invited
On 19 Oct, 2019
No comments provided
Editorial decision: Major revision
On 29 Aug, 2019
Review #2 received
Received 28 Aug, 2019
Review #1 received
Received 28 Aug, 2019
Reviewer #2 agreed
On 04 Aug, 2019
Reviewer #1 agreed
On 04 Aug, 2019
Reviewers invited
Invitations sent on 03 Jul, 2019
Submission checks complete
On 26 Jun, 2019
Editor invited
On 12 Jun, 2019
Editor assigned
On 12 Jun, 2019
First submitted
On 10 Jun, 2019
Metrics
Comments: 0
PDF Downloads: ...
HTML Views: ...
Subject Areas
Plant Molecular Biology and Genetics
Learn more about our company.
This preprint is under consideration at BMC Plant Biology. A preprint is a preliminary version of a manuscript that has not completed peer review at a journal. Research Square does not conduct peer review prior to posting preprints. The posting of a preprint on this server should not be interpreted as an endorsement of its validity or suitability for dissemination as established information or for guiding clinical practice.
Learn more about In Review
Research article
Characterization of a vacuolar sucrose transporter, HbSUT5, from Hevea brasiliensis: involvement in latex production through regulation of intracellular sucrose transport in the bark and laticifers
xiangyu long
Chinese Academy of Medical Sciences and Peking Union Medical College Hospital and Institute of Dermatology
Corresponding Author
Badges
Prescreen
This manuscript passed our Prescreen assessment
Complete author information
Appropriate declaration statements
Potential risks to human health
Prescreen
Peer Review Timeline
CURRENT STATUS: Published
Version 3
Posted 03 Jan, 2020
Published
On 27 Dec, 2019
No community comments so far
Editorial decision: Accept
On 18 Dec, 2019
Editor assigned
On 17 Dec, 2019
Submission checks complete
On 16 Dec, 2019
Editor invited
On 16 Dec, 2019
No comments provided
Editorial decision: Minor revision
On 16 Dec, 2019
Reviewer #1 agreed
On 22 Oct, 2019
Reviewers invited
Invitations sent on 21 Oct, 2019
Editor assigned
On 20 Oct, 2019
Submission checks complete
On 19 Oct, 2019
Editor invited
On 19 Oct, 2019
No comments provided
Editorial decision: Major revision
On 29 Aug, 2019
Review #2 received
Received 28 Aug, 2019
Review #1 received
Received 28 Aug, 2019
Reviewer #2 agreed
On 04 Aug, 2019
Reviewer #1 agreed
On 04 Aug, 2019
Reviewers invited
Invitations sent on 03 Jul, 2019
Submission checks complete
On 26 Jun, 2019
Editor invited
On 12 Jun, 2019
Editor assigned
On 12 Jun, 2019
First submitted
On 10 Jun, 2019
Metrics
Comments: 0
PDF Downloads: ...
HTML Views: ...
Subject Areas
Plant Molecular Biology and Genetics
License:
This work is licensed under a CC BY 4.0 License. Read Full License
View the published version at BMC Plant Biology.
Background: Sucrose (Suc), as the precursor molecule for rubber biosynthesis in Hevea brasiliensis , is transported via phloem-mediated long-distance transport from leaves to laticifers in trunk bark, where latex (cytoplasm of laticifers) is tapped for rubber. In our previous report, six Suc transporter (SUT) genes have been cloned in Hevea tree, among which HbSUT3 is verified to play an active role in Suc loading to the laticifers. In this study, another latex-abundant SUT isoform, HbSUT5 , with expressions only inferior to HbSUT3 was characterized especially for its roles in latex production. Results: Both phylogenetic analysis and subcellular localization identify HbSUT5 as a tonoplast-localized SUT protein under the SUT4-clade (=type III). Suc uptake assay in baker’s yeast reveals HbSUT5 to be a typical Suc-H + symporter, but its high affinity for Suc (Km = 2.03 mM at pH 5.5) and the similar efficiency in transporting both Suc and maltose making it a peculiar SUT under the SUT4-clade. At the transcript level, HbSUT5 is abundantly and preferentially expressed in Hevea barks. The transcripts of HbSUT5 are conspicuously decreased both in Hevea latex and bark by two yield-stimulating treatments of tapping and ethephon, the patterns of which are contrary to HbSUT3. Under the ethephon treatment, the Suc level in latex cytosol decreases significantly, but that in latex lutoids (polydispersed vacuoles) changes little, suggesting a role of the decreased HbSUT5 expression in Suc compartmentalization in the lutoids and thus enhancing the Suc sink strength in laticifers. Conclusions: Our findings provide insights into the roles of a vacuolar sucrose transporter, HbSUT5, in Suc exchange between lutoids and cytosol in rubber-producing laticifers.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5