English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Giardia lamblia  persists in a dormant state with a protective cyst wall for transmission. It is incompletely known how three cyst wall proteins (CWPs) are coordinately synthesized during encystation. Meiotic recombination is required for sexual reproduction in animals, fungi, and plants. It is initiated by formation of double-stranded breaks by a topoisomerase-like Spo11. It has been shown that exchange of genetic material in the fused nuclei occurs during  Giardia  encystation, suggesting parasexual recombination processes of this protozoan.  Giardia  possesses an evolutionarily conserved Spo11 with typical domains for cleavage reaction and an upregulated expression pattern during encystation. In this study, we asked whether Spo11 can activate encystation process, like other topoisomerases we previously characterized. We found that Spo11 was capable of binding to both single-stranded and double-stranded DNA in vitro and that it could also bind to the  cwp  promoters in vivo as accessed in chromatin immunoprecipitation assays. Spo11 interacted with WRKY and MYB2 (named from myeloblastosis), transcription factors that can activate  cwp  gene expression during encystation. Interestingly, overexpression of Spo11 resulted in increased expression of  cwp1 - 3  and  myb2  genes and cyst formation. Mutation of the Tyr residue for the active site or two conserved residues corresponding to key DNA-binding residues for  Arabidopsis  Spo11 reduced the levels of  cwp1-3  and  myb2  gene expression and cyst formation. Targeted disruption of  spo11  gene with CRISPR/Cas9 system led to a significant decrease in  cwp1-3  and  myb2  gene expression and cyst number. Our results suggest that Spo11 acts as a positive regulator for  Giardia  differentiation into cyst.

A Novel Spo11 Homologue Functions as a Positive Regulator in Cyst Differentiation in Giardia lamblia