This invention relates to isolated polynucleotides encoding BRITTLE STALK 2-like (Bk2L) family polypeptides. The invention also relates to the construction of a chimeric gene encoding all or a portion of a Bk2L polypeptide, in sense or antisense orientation, wherein expression of the chimeric gene results in production of altered levels of the Bk2L polypeptide in a transformed host cell.