Abstract:

In this study，the coding sequences of ubiquitin protein BoSU03 identified by Brassica
oleracea stigma protein mass spectrometry were amplified. Nucleotide sequence analysis showed that it
was highly identical with nucleotide sequence of ubiquitin protein Bol003815 in Brasscia oleracea，
BoSU03 contained ARM repeat domain and belonged to Plant U-box protein family. In order to analyze
the interaction between BoSU03 and SRK，GAL4 two-hybrid system was used here，and the interaction
between SRK and ARC1 was used as control. The results showed that the yeast cells transformed withBoSRK/BoSU03 could grow better and turn deeper blue on SD/-Ade/-His/-Leu/-Trp/x-α-gal/25 mmol
3-AT nutritional media. And the level of β-Galactosidase activity of BoSRK/BoSU03 was higher than that
of BoSRK/BoARC1. These results will provide the basis for further analysis whether BoSU03 participates
in SRK downstream SI signaling pathway.

Key words: Brasscia oleracea, S-locus receptor kinase（SRK）, BoSU03, Plant U-box family（PUB）,
downstream signaling protein, yeast two-hybrid system