Pollen-expressed S-RNases are not involved in self-incompatibility in Lycopersicon peruvianum

Abstract

Self-incompatibility in solanaceous plants is gametophytically controlled by a multiallelic S-locus. The only known S-locus product is a series of extracellular ribonucleases (the S-RNases) which are expressed in the mature style and determine its self-incompatibility phenotype. Potentially, S-RNases also determine the self-incompatibility phenotype of pollen as some solanaceous plants express this protein for a brief period during anther development. To test this, we first showed that the S3-RNase of Lycopersicon peruvianum is expressed during anther development. We then transformed L. peruvianum plants with sense and antisense versions of the S3RNase coding region under the control of a po..