[No authors listed]
Although excess boron (B) is known to negatively affect plant growth, its molecular mechanism of toxicity is unknown. We previously isolated two Arabidopsis thaliana mutants, hypersensitive to excess B (heb1-1 and heb2-1). In this study, we found that HEB1 and HEB2 encode the CAP-G2 and CAP-H2 subunits, respectively, of the condensin II protein complex, which functions in the maintenance of chromosome structure. Growth of Arabidopsis seedlings in medium containing excess B induced expression of condensin II subunit genes. Simultaneous treatment with zeocin, which induces DNA double-strand breaks (DSBs), and aphidicolin, which blocks DNA replication, mimicked the effect of excess B on root growth in the heb mutants. Both excess B and the heb mutations upregulated DSBs and DSB-inducible gene transcription, suggesting that DSBs are a cause of B toxicity and that condensin II reduces the incidence of DSBs. The Arabidopsis T-DNA insertion mutant atr-2, which is sensitive to replication-blocking reagents, was also sensitive to excess B. Taken together, these data suggest that the B toxicity mechanism in plants involves DSBs and possibly replication blocks and that plant condensin II plays a role in DNA damage repair or in protecting the genome from certain genotoxic stressors, particularly excess B.
KEYWORDS: {{ getKeywords(articleDetailText.words) }}
Sample name | Organism | Experiment title | Sample type | Library instrument | Attributes | |||||||||||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
{{attr}} | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
{{ dataList.sampleTitle }} | {{ dataList.organism }} | {{ dataList.expermentTitle }} | {{ dataList.sampleType }} | {{ dataList.libraryInstrument }} | {{ showAttributeName(index,attr,dataList.attributes) }} |
{{ list.authorName }} {{ list.authorName }} |