Research Interests

My laboratory is interested in the relationship between chromatin structure and gene function in animals and in plants. There is a growing recognition of the importance of chromatin structure and of the products of the Pc-G/Trx-G complex as part of a global cellular memory system. Despite the realization that these mechanisms are involved in processes regulating cell-fate and developmental programs, we still know little about the Pc-G/Trx-G functions and chromatin-regulated events in plants.

With the advent of new technologies and groundbreaking new studies, there is a renewed interest in exploring the possibilities for common mechanisms regulating development in animals and in plants.

We are studying a family of Trithorax related genes in the model plant Arabidopsis. We are studying its role in regulating flower development and the molecular/biochemical mechanism of its activity. The unexpected observation that some members of the family (ATX1) are not obligatory nuclear proteins and the determined ability of ATX1 to bind the phospholipid ligand, phosphoinositide-5 phosphate, opened a novel venue of our research: a current goal is to characterize this signaling mechanism connecting cellular signaling with epigenetic gene regulation. We are particularly interested in the evolution of these mechanisms at the molecular level and include a broad array of phylogenetic, bioinformatics, molecular and cellular biology approaches. 

Recent Publications

• Alvarez-Venegas R, Tikhonov A, Sadder M, and Avramova Z. (2007) Origin of the Bacterial SET Domain Genes: Vertical or Horizontal?  Mol Biol Evol 24, 482-497.    
• Alvarez-Venegas R, Xia Y, Lu G, and Avramova Z (2006) Phosphoinositide 5-Phosphate and Phosphoinositide 4-Phosphate Trigger Distinct Specific Responses of Arabidopsis Genes. Plant Signaling and Behavior 1, 140-151. 
• Alvarez-Venegas R, Sadder M, Hlavacka A,  Baluška F,  Xia Y, Lu G, Firsov A, Sarath G, Moriyama H, Dubrovsky J, and  Avramova Z (2006) The Arabidopsis Homolog of Trithorax, ATX1, Binds Phosphoinositide 5-Phosphate and the Two Regulate a Common Set of Target Genes. Proc. Natl. Acad. Sci. 103, 6049-6054
• Alvarez-Venegas R and Avramova Z (2005) Methylation Patterns of Histone H3 Lys 4, Lys 9 and Lys 27 in   transcriptionaly active and inactive Arabidopsis genes and in atx1 mutants. Nucl. Acids Res. 33, 5199-520
• Alvarez-Venegas, R., Pien, S., Sadder, M., Witmer, X., Grossniklaus, U., and Avramova, Z. (2003)  ATX-1, An Arabidopsis homolog of Trithorax has histone methylase activity and activates flower homeotic genes. Current Biol. 13, 627-637
• Alvarez-Venegas R, Yilmaz, M., Le O, Xia Y, Lu G, Hu G. and Avramova Z. Two Closely Related Members of the ATX Family Have Distinct Functions in Arabidopsis (submitted).
• Saleh A., Al-Abdallat  A., Ndamukong I, Alvarez-Venegas R, and Avramova Z. A Bivalent Chromatin Mark is Required for the Repression of the Flower Homeotic Gene AGAMOUS in Arabidopsis (submitted).
• Alvarez-Venegas R, Al-Abdallat A, Guo M, Alfano J. and Avramova Z.  Epigenetic Control of a Transcription Factor at the Node of Convergence of Two Signaling Pathways (submitted)
• Saleh A., Yilmaz M, Alvarez-Venegas R, and Avramova Z. The ARABIDOPSIS HOMOLOG OF TRITHORAX2, ATX2, encodes a putative histone H3-lysine 4 dimethylase (submitted)