Mendel
meets Molecules:
The Molecular Biology
of Round & Wrinkled
The difference
between Mendel's round
(R-) and wrinkled (rr) pea phenotypes is a
defect in starch-branching enzyme I (SBEI) that causes rr
seeds to lose water and hence turgor pressure, resulting in a wrinkled
phenotype. The r allele is produced by a transposable element.