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Using Ustilago maydis as a Trojan Horse for In Situ Delivery of Maize Proteins
Published on: February 8, 2019
Maize ROP2 GTPase provides a competitive advantage to the male gametophyte
K M Arthur1, Z Vejlupkova, R B Meeley
1Center for Gene Research and Biotechnology and Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon 97331, USA.
Genetics
|January 6, 2004
Summary
ROP2 (Ras-related C3 botulinum toxin substrate 2) is crucial for maize male gametophyte function. Mutations in ROP2 impair pollen transmission, indicating a competitive disadvantage for mutant pollen.
Area of Science:
- Plant molecular biology
- Genetics
- Cell signaling
Background:
- ROP GTPases regulate plant signal transduction and cell morphogenesis.
- ROP2 is a member of the ROP GTPase family in maize.
Purpose of the Study:
- To investigate the function of ROP2 in maize.
- To analyze the effects of ROP2 mutations on male gametophyte transmission.
Main Methods:
- Isolation of Mutator transposon insertions (rop2::Mu alleles).
- Analysis of transmission frequency through male and female gametophytes.
- Assessment of ROP2-mRNA levels in pollen.
Main Results:
- Three out of five rop2::Mu alleles showed reduced transmission frequency through the male gametophyte.
- Reduced ROP2-mRNA levels in pollen correlated with transmission defects.
- Mutant pollen exhibited a competitive disadvantage against wild-type pollen.
Conclusions:
- ROP2 plays a critical role in maize male gametophyte function.
- ROP2 is essential for competitive success of pollen, despite a lack of obvious cellular defects.
- The findings highlight the in vivo importance of ROP2 in the male gametophyte.
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