Skip Navigation

This Article
Right arrow Full Text Freely available
Right arrow Print PDF (291K) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (10)
Right arrowRequest Permissions
Right arrow Commercial Re-use Guidelines
for Open Access NAR Content
Google Scholar
Right arrow Articles by Tron, A. E.
Right arrow Articles by Gonzalez, D. H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Tron, A. E.
Right arrow Articles by Gonzalez, D. H.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Nucleic Acids Research, 2001, Vol. 29, No. 23 4866-4872
© 2001 Oxford University Press

Combinatorial interactions of two amino acids with a single base pair define target site specificity in plant dimeric homeodomain proteins

Adriana E. Tron, Carlos W. Bertoncini, Claudia M. Palena, Raquel L. Chan and Daniel H. Gonzalez*

Cátedra de Biología Celular y Molecular, Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, CC 242 Paraje El Pozo, 3000 Santa Fe, Argentina

Four groups of plant homeodomain proteins contain a dimerization motif closely linked to the homeodomain. We here show that two sunflower homeodomain proteins, Hahb-4 and HAHR1, which belong to the Hd-Zip I and GL2/Hd-Zip IV groups, respectively, show different binding preferences at a defined position of a pseudopalindromic DNA-binding site used as a target. HAHR1 shows a preference for the sequence 5'-CATT(A/T)AATG-3', rather than 5'-CAAT(A/T)ATTG-3', recognized by Hahb-4. To analyze the molecular basis of this behavior, we have constructed a set of mutants with exchanged residues (Phe->Ile and Ile->Phe) at position 47 of the homeodomain, together with chimeric proteins between HAHR1 and Hahb-4. The results obtained indicate that Phe47, but not Ile47, allows binding to 5'-CATT(A/T)AATG-3'. However, the preference for this sequence is determined, in addition, by amino acids located C-terminal to residue 53 of the HAHR1 homeodomain. A double mutant of Hahb-4 (Ile47->Phe/Ala54->Thr) shows the same binding behavior as HAHR1, suggesting that combinatorial interactions of amino acid residues at positions 47 and 54 of the homeodomain are involved in establishing the affinity and selectivity of plant dimeric homeodomain proteins with different DNA target sequences.

* To whom correspondence should be addressed. Tel: +54 342 4575219; Fax: +54 342 4575219; Email: dhgonza{at}fbcb.unl.edu.ar


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Plant CellHome page
S. Wenkel, J. Emery, B.-H. Hou, M. M.S. Evans, and M.K. Barton
A Feedback Regulatory Module Formed by LITTLE ZIPPER and HD-ZIPIII Genes
PLANT CELL, November 1, 2007; 19(11): 3379 - 3390.
[Abstract] [Full Text] [PDF]

Home page
 Plant Physiol.Home page
M. Nakamura, H. Katsumata, M. Abe, N. Yabe, Y. Komeda, K. T. Yamamoto, and T. Takahashi
Characterization of the Class IV Homeodomain-Leucine Zipper Gene Family in Arabidopsis
Plant Physiology, August 1, 2006; 141(4): 1363 - 1375.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
A. E. Tron, C. W. Bertoncini, R. L. Chan, and D. H. Gonzalez
Redox Regulation of Plant Homeodomain Transcription Factors
J. Biol. Chem., September 13, 2002; 277(38): 34800 - 34807.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.