University of Cambridge
Cambridge CB2 3EA
Positioning of crossovers along chromosomes is non-random, with transcriptionally active chromatin undergoing more crossovers than heterochromatic centromere-proximal regions. Although chromatin structure has been implicated in determining crossover distribution along chromosomes, the mechanisms remain elusive. My main research interest is whether epigenetic information, in particular, cytosine DNA methylation is implicated in shaping the crossover landscape. Arabidopsis thaliana DNA methyltransferase1 (met1) mutants show genome-wide demethylation, with greatest decrease in the centromere-proximal regions where DNA methylation transcriptionally silences repetitive elements. I have observed that while DNA hypomethylation in met1 does not affect total genetic length it causes a remodeling of crossover distributions along Arabidopsis chromosomes. I am currently developing assays to directly analyse how epigenetic marks modulate the activity of meiotic recombination hotspots and developing a genome-wide assay to map meiotic-specific double-stranded breaks in Arabidopsis. I am employing a number of techniques that allow the analysis of a large number of crossover events, i.e. a recently developed fluorescent pollen tetrad (FTL) analysis (in collaboration with Prof. Copenhavers's lab, University of North Carolina, USA) and a seed-based segregation analysis (in collaboration with Prof. A. Levi's lab, Weizmann Institute of Science, Israel). Additionally, I have combined the FTL approach with flow cytometry to develop, in collaboration with Nigel Miller, Department of Pathology, University of Cambridge, UK, a new high throughput technique to measure crossovers.
Yelina N., Smith L.M., Jones, A., Patel K, Kelly, K.A. and Baulcombe D.C. (2010) A Putative Arabidopsis THO/TREX mRNA Export Complex Is Involved in Transgene and Endogenous siRNA Biosynthesis. Proc Natl Acad Sci U S A, 107(31):13948-53.
MacLean D., Elina N., Havecker E.R., Heimstaedt S.B., Studholme D.J., Baulcombe D.C. (2010) Evidence for large complex networks of plant short silencing RNAs. PLoS One, 5(3):e9901.
Smith L.M., Pontes O., Searle I., Yelina N., Yousafzai F.K., Pikaard C.S., and Baulcombe D.C. (2007). A novel SNF2 helicase associated with nuclear RNA silencing and spread of a silencing signal between cells. Plant Cell, 19(5):1507-21.
Hernandez-Pinzon I., Yelina N.E., Schwach F., Studholme D.J., Baulcombe D.C. and Dalmay T. (2007) SDE5 - the putative homologue of a human mRNA export factor is required for transgene silencing and accumulation of trans-acting endogenous siRNA. Plant Journal, 50(1):140-8.
Rakitina D.V., Yelina N.E., Kalinina N.O. (2006) Zinc ions stimulate the cooperative RNA binding of hordeiviral gamma-b protein. FEBS Letters 580, 5077-83.
Lukhovitskaya* N.I., Yelina* N.E., Zamyatnin A.A. Jr., Schepetilnikov M.V., Solovyev A.G., Sandgren M., Morozov S.Y., Valkonen J.P., Savenkov E.I. (2005) Expression, localization and effects on virulence of the cysteine-rich 8 kDa protein of Potato mop-top virus. Journal of General Virology, 86, 2879-89. (* joint first authors)
Yelina N. E., Erokhina T. N., Lukhovitskaya N. I., Minina E. A., Schepetilnikov M. V., Lesemann D.-E., Schiemann J., Solovyev A. G. and Morozov S. Yu. (2005). Localization of Poa semilatent virus cysteine-rich protein in peroxisomes is dispensable for its ability to suppress RNA silencing. Journal of General Virology, 86, 479-89.
Gorshkova E. N., Erokhina T. N., Stroganova T. A., Yelina N.E., Zamyatnin A. A. Jr, Kalinina N. O., Schiemann J., Solovyev A. G., Morozov S.Y. (2003). Immunodetection and fluorescent microscopy of transgenically expressed hordeivirus TGBp3 movement protein reveals its association with endoplasmic reticulum elements in close proximity to plasmodesmata. Journal of General Virology, 84, 985-94.
Yelina N.E., Savenkov, E. I., Solovyev, A. G., Morozov S. Y., and Valkonen J. P. (2002). Long-distance movement, virulence, and RNA silencing suppression controlled by a single protein in Hordei- and Potyviruses: Complementary functions between virus families. Journal of Virology, 76, 12981-91.
Fedorkin O. N., Solovyev A. G., Yelina N.E., Zamyatnin A. A. Jr., Zinovkin R. A., Makinen K., Schiemann J., Morozov S.Yu.. (2001). Cell-to-cell movement of potato virus X involves distinct functions of the coat protein. Journal of General Virology, 82, 449-458.
Kalinina N. O., Rakitina D. A., Yelina N.E., Zamyatnin A. A. Jr., Stoganova T. A., Klinov D. V., Prokhorov V. V., Ustinova S. V., Chernov B. K., Schiemann J., Solovyev A. G., and Morozov S. Yu. (2001). RNA-binding properties of the 63-kDa protein encoded by the triple gene block of poa semilatent horedivirus. Journal of General Virology, 82, 2569-78.