(My CV in PDF)

 

I am a fourth year graduate student in the department of Plant Cellular and Molecular Biology (PCMB) and in my third year in the Grotewold lab.

The Grotewold lab is made up of a diverse set of students, postdocs and visiting scientists. Not only is the lab made up of diverse people, but also the projects in which they are involved are truly diverse. This mixture of diversity always leads to exciting conversations and activities. The stimulation in lab from the lab members and the science always finds a way to integrate itself in to my day and making for some stimulating times in the lab.

In general, I have thus far been investigating the mechanisms by which the maize C1 and P1 R2R3 MYB transcription factors control the expression of overlapping sets of flavonoid biosynthetic genes. I have also been involved with a project in which we have gained further understanding of two mechanisms by which R, a bHLH transcription factor, contributes to the regulatory activity of C1.

More specifically, we have established that a novel REDOX mechanism in which two closely positioned Cys residues participate in the control of DNA-binding by the R2R3 transcription factor, P1. The conserved position of these two Cys residues in 100+ Arabidopsis R2R3 MYB transcription factors suggest that REDOX regulation might be a general characteristic of members of this large family of regulatory proteins.

This REDOX regulation of the MYB family in plants, due to the presence of two Cys residues, is fundamentally different from the REDOX regulation of the MYB family in other eukaryotic organisms, which contain only one conserved Cys residue.

In the future, I would like to finish a couple of projects I have ongoing in the lab.

First, I would like to finish the molecular dissection of the P1 protein to establish whether the MYB domain is sufficient for DNA-binding in vivo and to determine whether P1 has a transcription activation domain. To wrap up this project, I have enlisted the help of a very talented undergraduate, David Ciarlariello .

Second, I am close to finishing an analysis of mutants in the R2R3 MYB domain of P1 that reconstruct the main evolutionary steps that shaped the origin of R2R3 MYB proteins from broadly distributed R1R2R3 MYB transcription factors. Finally, I am characterizing R2R3 MYB domain specific monoclonal antibodies that selectively recognize oxidized or reduced MYB conformers.

 

Related Publications

Heine GF, Hernandez MJ, Grotewold E (2004) Two cysteines in plant R2R3 MYB domains participate in REDOX-dependent DNA binding. J. Biol. Chem. 279: 37878-37885

Hernandez MJ, Heine G, Irani NG, Feller A, Kim M-G, Matulnik T, Chandler VL, Grotewold E (2004) Mechanisms of cooperation between MYB and HLH transcription factors in the regulation of anthocyanin pigmentation. J. Biol. Chem. 279: 48205-48213