The secret of why plants grow to the right or left

Like humans with their left-sided hearts, plants also can display asymmetric forms, such as helically twisted flowers and tendrils. A team of Yale scientists have recently discovered a mechanism that controls whether plant organs are helical.

Professor Vivian Irish and postdoctoral associate Adam Saffer of the Department of Molecular, Cellular and Developmental Biology report that asymmetry in plants can be caused by changes in pectin, a component of the surface of plant cells and a substance that gives jam its gelatinous quality. These alterations in pectin lead to left-handed twisting of petals and other organs, as they report in the August 7 issue of Current Biology.

The insights can help explain why many garden plants take on unusual shapes. Understanding how pectin can control plant shape may one day help scientists engineer new biomaterials based on the unusual properties of pectin, the authors say.