Mutations at the rug4 locus alter the carbon and nitrogen metabolism of pea plants through an effect on sucrose synthase

Mutations at the rug4 locus alter the carbon and nitrogen metabolism of pea plants through an... Summary The biochemical and molecular basis of the wrinkled‐seeded phenotype of rug4 mutants of pea ( Pisum sativum L.) has been investigated. Mutant embryos have reduced starch contents and only 5% of the sucrose synthase activity of wild‐type embryos during development. Activities of other enzymes involved in the conversion of sucrose to starch are unaffected. A gene encoding an isoform of sucrose synthase expressed in the embryo co‐segregates with the rug4 locus, and one of the three mutant alleles has been show to carry a point mutation in this gene that converts a highly conserved arginine residue to a lysine residue. It is highly likely that the reduced starch content of the mutant embryo is a direct consequence of the loss of sucrose synthase activity. The mutations reduce the activity of sucrose synthase in the testa and the leaf by 50% or less, but activity in Rhizobium ‐infected root nodules is reduced by 85%. Although the nodules of mutant plants contain metabolically active bacteroids, the N content and δ15N values of these plants in the field indicate that, unlike wild‐type plants, they derive little of their N from N2 fixation via Rhizobium . Sucrose synthase thus appears to be essential for the supply of carbon for bacteroid metabolism and/or ammonia assimilation during nitrogen assimilation. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The Plant Journal Wiley

Mutations at the rug4 locus alter the carbon and nitrogen metabolism of pea plants through an effect on sucrose synthase

Loading next page...
 
/lp/wiley/mutations-at-the-rug4-locus-alter-the-carbon-and-nitrogen-metabolism-YJpOMzUKew
Publisher
Wiley
Copyright
Copyright © 1999 Wiley Subscription Services, Inc., A Wiley Company
ISSN
0960-7412
eISSN
1365-313X
D.O.I.
10.1046/j.1365-313X.1999.00382.x
Publisher site
See Article on Publisher Site

Abstract

Summary The biochemical and molecular basis of the wrinkled‐seeded phenotype of rug4 mutants of pea ( Pisum sativum L.) has been investigated. Mutant embryos have reduced starch contents and only 5% of the sucrose synthase activity of wild‐type embryos during development. Activities of other enzymes involved in the conversion of sucrose to starch are unaffected. A gene encoding an isoform of sucrose synthase expressed in the embryo co‐segregates with the rug4 locus, and one of the three mutant alleles has been show to carry a point mutation in this gene that converts a highly conserved arginine residue to a lysine residue. It is highly likely that the reduced starch content of the mutant embryo is a direct consequence of the loss of sucrose synthase activity. The mutations reduce the activity of sucrose synthase in the testa and the leaf by 50% or less, but activity in Rhizobium ‐infected root nodules is reduced by 85%. Although the nodules of mutant plants contain metabolically active bacteroids, the N content and δ15N values of these plants in the field indicate that, unlike wild‐type plants, they derive little of their N from N2 fixation via Rhizobium . Sucrose synthase thus appears to be essential for the supply of carbon for bacteroid metabolism and/or ammonia assimilation during nitrogen assimilation.

Journal

The Plant JournalWiley

Published: Feb 1, 1999

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