Increased capacity for sucrose uptake leads to earlier onset of protein accumulation in developing pea seeds

Increased capacity for sucrose uptake leads to earlier onset of protein accumulation in... Pea ( Pisum sativum L.) cotyledons, overexpressing a potato sucrose transporter ( StSUT1 ), were used to explore the hypothesis that sucrose stimulates the onset of storage protein biosynthesis. The study focused on the transition between pre-storage and storage phases of seed development. During this period supply of sucrose and hexose to transgenic cotyledons was unaffected by StSUT1 expression. However, protoplasmic levels of sucrose but not hexoses were elevated in transgenic cotyledons. Total protein levels in cotyledons followed the same temporal trend as observed for sucrose and this was reflected in an earlier appearance of protein bodies. Protein levels in wild type and StSUT1 cotyledons were found to lie on the same sucrose dose-response curve and this could be reproduced in vitro when wild type cotyledons were cultured on media containing various sucrose concentrations. Rates of ( 14 C)sucrose uptake and incorporation into polymeric forms were consistent with protoplasmic sucrose supplying a proportion of the carbon skeletons required for storage protein accumulation. In addition, vicilin gene expression was up-regulated earlier in StSUT1 cotyledons. We conclude that sucrose functions both as a signal and fuel to stimulate storage protein accumulation and assembly into protein bodies. An earlier stimulation of storage protein synthesis is considered to largely account for the 14% increase in protein levels of StSUT1 seeds at harvest. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Functional Plant Biology CSIRO Publishing

Increased capacity for sucrose uptake leads to earlier onset of protein accumulation in developing pea seeds

Loading next page...
 
/lp/csiro-publishing/increased-capacity-for-sucrose-uptake-leads-to-earlier-onset-of-VRz0Ijax8g
Publisher
CSIRO Publishing
Copyright
CSIRO
ISSN
1445-4408
eISSN
1445-4416
D.O.I.
10.1071/FP05127
Publisher site
See Article on Publisher Site

Abstract

Pea ( Pisum sativum L.) cotyledons, overexpressing a potato sucrose transporter ( StSUT1 ), were used to explore the hypothesis that sucrose stimulates the onset of storage protein biosynthesis. The study focused on the transition between pre-storage and storage phases of seed development. During this period supply of sucrose and hexose to transgenic cotyledons was unaffected by StSUT1 expression. However, protoplasmic levels of sucrose but not hexoses were elevated in transgenic cotyledons. Total protein levels in cotyledons followed the same temporal trend as observed for sucrose and this was reflected in an earlier appearance of protein bodies. Protein levels in wild type and StSUT1 cotyledons were found to lie on the same sucrose dose-response curve and this could be reproduced in vitro when wild type cotyledons were cultured on media containing various sucrose concentrations. Rates of ( 14 C)sucrose uptake and incorporation into polymeric forms were consistent with protoplasmic sucrose supplying a proportion of the carbon skeletons required for storage protein accumulation. In addition, vicilin gene expression was up-regulated earlier in StSUT1 cotyledons. We conclude that sucrose functions both as a signal and fuel to stimulate storage protein accumulation and assembly into protein bodies. An earlier stimulation of storage protein synthesis is considered to largely account for the 14% increase in protein levels of StSUT1 seeds at harvest.

Journal

Functional Plant BiologyCSIRO Publishing

Published: Oct 28, 2005

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create folders to
organize your research

Export folders, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off