{"title":"Target degradation specificity of phytoplasma effector phyllogen is regulated by the recruitment of host proteasome shuttle protein.","authors":"Masato Suzuki, Yugo Kitazawa, Nozomu Iwabuchi, Kensaku Maejima, Juri Matsuyama, Oki Matsumoto, Kenro Oshima, Shigetou Namba, Yasuyuki Yamaji","doi":"10.1111/mpp.13410","DOIUrl":null,"url":null,"abstract":"<p><p>Phytoplasmas infect a wide variety of plants and can cause distinctive symptoms including the conversion of floral organs into leaf-like organs, known as phyllody. Phyllody is induced by an effector protein family called phyllogens, which interact with floral MADS-box transcription factors (MTFs) responsible for determining the identity of floral organs. The MTF/phyllogen complex then interacts with the proteasomal shuttle protein RADIATION SENSITIVE23 (RAD23), which facilitates delivery of the MTF/phyllogen complex to the host proteasome for MTF degradation. Previous studies have indicated that the MTF degradation specificity of phyllogens is determined by their ability to bind to MTFs. However, in the present study, we discovered a novel mechanism determining the degradation specificity through detailed functional analyses of a phyllogen homologue of rice yellow dwarf phytoplasma (PHYL<sub>RYD</sub> ). PHYL<sub>RYD</sub> degraded a narrower range of floral MTFs than other phyllody-inducing phyllogens, resulting in compromised phyllody phenotypes in plants. Interestingly, PHYL<sub>RYD</sub> was able to bind to some floral MTFs that PHYL<sub>RYD</sub> was unable to efficiently degrade. However, the complex of PHYL<sub>RYD</sub> and the non-degradable MTF could not interact with RAD23. These results indicate that the MTF degradation specificity of PHYL<sub>RYD</sub> is correlated with the ability to form the MTF/PHYL<sub>RYD</sub> /RAD23 ternary complex, rather than the ability to bind to MTF. This study elucidated that phyllogen target specificity is regulated by both the MTF-binding ability and RAD23 recruitment ability of the MTF/phyllogen complex.</p>","PeriodicalId":18763,"journal":{"name":"Molecular plant pathology","volume":null,"pages":null},"PeriodicalIF":4.8000,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10799209/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Molecular plant pathology","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.1111/mpp.13410","RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2023/12/17 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"PLANT SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Phytoplasmas infect a wide variety of plants and can cause distinctive symptoms including the conversion of floral organs into leaf-like organs, known as phyllody. Phyllody is induced by an effector protein family called phyllogens, which interact with floral MADS-box transcription factors (MTFs) responsible for determining the identity of floral organs. The MTF/phyllogen complex then interacts with the proteasomal shuttle protein RADIATION SENSITIVE23 (RAD23), which facilitates delivery of the MTF/phyllogen complex to the host proteasome for MTF degradation. Previous studies have indicated that the MTF degradation specificity of phyllogens is determined by their ability to bind to MTFs. However, in the present study, we discovered a novel mechanism determining the degradation specificity through detailed functional analyses of a phyllogen homologue of rice yellow dwarf phytoplasma (PHYLRYD ). PHYLRYD degraded a narrower range of floral MTFs than other phyllody-inducing phyllogens, resulting in compromised phyllody phenotypes in plants. Interestingly, PHYLRYD was able to bind to some floral MTFs that PHYLRYD was unable to efficiently degrade. However, the complex of PHYLRYD and the non-degradable MTF could not interact with RAD23. These results indicate that the MTF degradation specificity of PHYLRYD is correlated with the ability to form the MTF/PHYLRYD /RAD23 ternary complex, rather than the ability to bind to MTF. This study elucidated that phyllogen target specificity is regulated by both the MTF-binding ability and RAD23 recruitment ability of the MTF/phyllogen complex.
期刊介绍:
Molecular Plant Pathology is now an open access journal. Authors pay an article processing charge to publish in the journal and all articles will be freely available to anyone. BSPP members will be granted a 20% discount on article charges. The Editorial focus and policy of the journal has not be changed and the editorial team will continue to apply the same rigorous standards of peer review and acceptance criteria.