>A colleague of mine has asked me what is known about the molecular basis
>of the various mutants that Mendel worked with.
>>Thanks in advance,
>U. Colorado, Boulder
>greenbej at beagle.colorado.edu
Here is one reference, there may be others...
M. K. Bhattacharyya, A. M. Smith, T. H. Ellis, C. Hedley, C. Martin, Cell
60, 115-22 (1990).
We describe the cloning of the r (rugosus) locus of pea (Pisum sativum L.),
which determines whether the seed is round or wrinkled. Wrinkled (rr) seeds
lack one isoform of starch-branching enzyme (SBEI), present in round (RR or
Rr) seeds. A major polymorphism in the SBEI gene between near-isogenic RR
and rr lines shows 100% cosegregation with the r locus, establishing that
the SBEI gene is at the r locus. An aberrant transcript for SBEI is
produced in rr embryos. In rr lines the SBEI gene is interrupted by a 0.8
kb insertion that is very similar to the Ac/Ds family of transposable
elements from maize. Failure to produce SBEI has complex metabolic
consequences on starch, lipid, and protein biosynthesis in the seed.
Brian I. Osborne bosborne at nature.berkeley.edu
Plant Gene Expression Center FAX 510 559 5718
800 Buchanan St. TEL 510 559 5919
Albany CA 94710 USA http://pgebaker4.pw.usda.gov/bio/bio.html