We screened for pollen-specific kinase genes, which are potential signal transduction components of pollen-pistil interactions, and isolated two structurally related receptor-like kinases (RLKs) from tomato, LePRK1 and LePRK2. These kinases are similar to a pollen-expressed RLK from petunia, but they are expressed later during pollen development than is the petunia RLK. The abundance of LePRK2 ...

Biochemical interactions between the pollen and the pistil allow plants fine control over fertilization. S-RNase-based pollen rejection is among the most widespread and best understood of these interactions. At least three plant families have S-RNase-based self-incompatibility (SI) systems, and S-RNases have also been implicated in interspecific pollen rejection. Although S-RNases determine the...

The promoter of the S Locus Glycoprotein (SLG) gene of Brassica is a tightly regulated promoter that is active specifically in reproductive organs. In transgenic tobacco, this promoter is active exclusively in cells of the pistil and in pollen. We transformed tobacco with truncated versions of the SLG13 promoter fused to the beta-glucuronidase reporter gene. We show that the promoter has a modu...

In some families of flowering plants, a single self-incompatibility (S) locus prevents the fertilization of flowers by pollen from the same plant. Self-incompatibility of this type involves the interaction of molecules produced by the S locus in pollen with those present in the female tissues (pistil). Until recently, the pistil products of the S locus were known in only two families, the Brass...

The success of sexual plant reproduction is directly influenced by specific interactions between the pollen and pistil. Light, fluorescence and scanning electron microscopy techniques were used to evaluate the steps of pollination in sour passion fruit plants (Passiflora edulis Sims). In the compatible interaction, pollen tubes grow through stigma projections towards the ovary. The pollen grain...

The cultivated almond displays a gametophytic self-incompatibility system, which avoids self-fertilization, and it is controlled by multi-allelic locus (S-locus) containing two genes specifically expressed in pistil (S-RNase) pollen (SFB). Studies on almonds with the same S-haplotype but different phenotype pointed to existence of unknown components this system explain its functioning. increase...

Prunus (Rosaceae) includes many commercially important fruit crop species that exhibit self-incompatibility (SI), including sweet cherry (P. avium L.), Japanese apricot mume Sieb. et Zucc.), plum salicina Lindl.), armeniaca and almond dulcis [Mill.] D. A. Webb.). These S-ribonuclease-based gametophytic SI, which prevents self-pollen tube growth in the pistil. The successful production of self-f...

INTRODUCTION ' The extremely reduced, three-celled, haploid male plant (male gametophyte) of flowering plants has a number of specialized functions to perform. The primary functions are the production of two sperm cells and their transport within the pollen tube through the tissues of the style and ovary into the embryo sac in the ovule, where they participate in double fertilization. The early...

Plants being sessile by nature have developed sophisticated mechanisms to assist in their selection of mating partners. During a compatible pollination event, pollen grains that have landed on the stigmatic surface at the top of the pistil will adhere to the stigmatic cells, hydrate, germinate and form pollen tubes. The actively growing pollen tubes are often capable of penetrating the stigmati...