Abstract:
:A major question in plant physiology is how the large amount of sucrose made in leaves is transported to the rest of the plant. Although physiological, biochemical, and anatomical investigations have been performed in this field, to date there have been very few genetic studies. Using a reverse genetic screen, we have identified mutant Arabidopsis plants containing transferred DNA insertions in the gene encoding a phloem-specific sucrose transporter, SUC2. SUC2 is thought to function in loading sugar from the apoplast into the conducting sieve tubes. In the homozygous state, these mutations resulted in stunted growth, retarded development, and sterility. The source leaves of mutant plants contained a great excess of starch, and radiolabeled sugar failed to be transported efficiently to roots and inflorescences. These data provide genetic proof that apoplastic phloem loading is critical for growth, development, and reproduction in Arabidopsis and that SUC2 is at least partially responsible for this step.
journal_name
Proc Natl Acad Sci U S Aauthors
Gottwald JR,Krysan PJ,Young JC,Evert RF,Sussman MRdoi
10.1073/pnas.250473797keywords:
subject
Has Abstractpub_date
2000-12-05 00:00:00pages
13979-84issue
25eissn
0027-8424issn
1091-6490pii
250473797journal_volume
97pub_type
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