Functional characterization of two chimeric proteins between a Petunia inflata S-locus F-box protein, PiSLF2, and a PiSLF-like protein, PiSLFLb-S2

Functional characterization of two chimeric proteins between a Petunia inflata S-locus F-box... Self-incompatible solanaceous species possess the S-RNase and SLF (S-locus F-box) genes at the highly polymorphic S-locus, and their products mediate S-haplotype-specific rejection of pollen tubes in the style. After a pollen tube grows into the style, the S-RNases produced in the style are taken up; however, only self S-RNase (product of the matching S-haplotype) can inhibit the subsequent growth of the pollen tube. Based on the finding that non-self interactions between PiSLF (Petunia inflata SLF) and S-RNase are stronger than self-interactions, and based on the biochemical properties of PiSLF, we previously proposed that a PiSLF preferentially interacts with its non-self S-RNases to mediate their ubiquitination and degradation, thereby only allowing self S-RNase to exert its cytotoxic function. We further divided PiSLF into three potential Functional Domains (FDs), FD1-FD3, based on sequence comparison of PiSLF and PiSLF-like proteins, and based on S-RNase-binding properties of these proteins and various truncated forms of PiSLF2 (S 2 allelic variant of PiSLF). In this work, we examined the in vivo function of FD2, which we proposed to be responsible for strong, general interactions between PiSLF and S-RNase. We swapped FD2 of PiSLF2 with the corresponding region of PiSLFLb-S2 (S 2 allelic variant of a PiSLF-like protein), and expressed GFP-fused chimeric proteins, named b-2-b and 2-b-2, in S 2 S 3 transgenic plants. We showed that neither chimeric protein retained the SI function of PiSLF2, suggesting that FD2 is necessary, but not sufficient, for the function of PiSLF. Moreover, since we previously found that b-2-b and 2-b-2 only interacted with S3-RNase ~50 and ~30%, respectively, as strongly as did PiSLF2 in vitro, their inability to function as PiSLF2 is also consistent with our model predicating on strong interaction between a PiSLF and its non-self S-RNases as part of the biochemical basis for S-haplotype-specific rejection of pollen tubes. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Plant Molecular Biology Springer Journals

Functional characterization of two chimeric proteins between a Petunia inflata S-locus F-box protein, PiSLF2, and a PiSLF-like protein, PiSLFLb-S2

Loading next page...
 
/lp/springer_journal/functional-characterization-of-two-chimeric-proteins-between-a-petunia-pgaTJ2UhXw
Publisher
Springer Netherlands
Copyright
Copyright © 2010 by Springer Science+Business Media B.V.
Subject
Life Sciences; Plant Pathology; Biochemistry, general; Plant Sciences
ISSN
0167-4412
eISSN
1573-5028
D.O.I.
10.1007/s11103-010-9672-x
Publisher site
See Article on Publisher Site

Abstract

Self-incompatible solanaceous species possess the S-RNase and SLF (S-locus F-box) genes at the highly polymorphic S-locus, and their products mediate S-haplotype-specific rejection of pollen tubes in the style. After a pollen tube grows into the style, the S-RNases produced in the style are taken up; however, only self S-RNase (product of the matching S-haplotype) can inhibit the subsequent growth of the pollen tube. Based on the finding that non-self interactions between PiSLF (Petunia inflata SLF) and S-RNase are stronger than self-interactions, and based on the biochemical properties of PiSLF, we previously proposed that a PiSLF preferentially interacts with its non-self S-RNases to mediate their ubiquitination and degradation, thereby only allowing self S-RNase to exert its cytotoxic function. We further divided PiSLF into three potential Functional Domains (FDs), FD1-FD3, based on sequence comparison of PiSLF and PiSLF-like proteins, and based on S-RNase-binding properties of these proteins and various truncated forms of PiSLF2 (S 2 allelic variant of PiSLF). In this work, we examined the in vivo function of FD2, which we proposed to be responsible for strong, general interactions between PiSLF and S-RNase. We swapped FD2 of PiSLF2 with the corresponding region of PiSLFLb-S2 (S 2 allelic variant of a PiSLF-like protein), and expressed GFP-fused chimeric proteins, named b-2-b and 2-b-2, in S 2 S 3 transgenic plants. We showed that neither chimeric protein retained the SI function of PiSLF2, suggesting that FD2 is necessary, but not sufficient, for the function of PiSLF. Moreover, since we previously found that b-2-b and 2-b-2 only interacted with S3-RNase ~50 and ~30%, respectively, as strongly as did PiSLF2 in vitro, their inability to function as PiSLF2 is also consistent with our model predicating on strong interaction between a PiSLF and its non-self S-RNases as part of the biochemical basis for S-haplotype-specific rejection of pollen tubes.

Journal

Plant Molecular BiologySpringer Journals

Published: Aug 11, 2010

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Unlimited reading

Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.

Stay up to date

Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.

Organize your research

It’s easy to organize your research with our built-in tools.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve Freelancer

DeepDyve Pro

Price
FREE
$49/month

$360/year
Save searches from
Google Scholar,
PubMed
Create lists to
organize your research
Export lists, citations
Read DeepDyve articles
Abstract access only
Unlimited access to over
18 million full-text articles
Print
20 pages/month
PDF Discount
20% off