@article {480,
	title = {Oligomerization-dependent association of the SAM domains from Schizosaccharomyces pombe Byr2 and Ste4},
	journal = {Journal of Biological Chemistry},
	volume = {277},
	number = {42},
	year = {2002},
	note = {ISI Document Delivery No.: 605EATimes Cited: 21Cited Reference Count: 46},
	month = {Oct},
	pages = {39585-39593},
	type = {Article},
	abstract = {SAM (sterile alpha motif) domains are protein-protein interaction modules found in a large number of regulatory proteins. Byr2 and Ste4 are two SAM domain-containing proteins in the mating pheromone response pathway of the fission yeast, Schizosaccharomyces pombe. Byr2 is a mitogen-activated protein kinase kinase kinase that is regulated by Ste4. Tu et al (Tu, H., Barr, M., Dong, D. L., and Wigler, M. (1997) Mol. Cell. Biol. 17, 5876-5887) showed that the isolated SAM domain of Byr2 binds a fragment of Ste4 that contains both a leucine zipper (Ste4-LZ) domain as well as a SAM domain, suggesting that Byr2-SAM and Ste4-SAM may form a hetero-oligomer. Here, we show that the individual SAM domains of Ste4 and Byr2 are monomeric at low concentrations and bind to each other in a 1:1 stoichiometry with a relatively weak dissociation constant of 56 +/- 3 mum. Inclusion of the Ste4-LZ domain, which determines the oligomeric state of Ste4, has a dramatic effect on binding affinity, however. We find that the Ste4-LZ domain is trimeric and, when included with the Ste4-SAM domain, yields a 3:1 Ste4-LZ-SAM:Byr2-SAM complex with a tight dissociation constant of 19 +/- 4 nm. These results suggest that the Ste4-LZ-SAM protein may recognize multiple binding sites on Byr2-SAM, indicating a new mode of oligomeric organization for SAM domains. The fact that high affinity binding occurs only with the addition of an oligomerization domain suggests that it may be necessary to include ancillary oligomerization modules when searching for binding partners of SAM domains.},
	keywords = {CRYSTAL-STRUCTURE, HUMAN LEUKEMIA, IDENTIFICATION, KINASE, LAC REPRESSOR, PROTEIN-KINASE, RECEPTOR, TEL, TRANSCRIPTION FACTOR, TYROSINE, YEAST},
	isbn = {0021-9258},
	url = {<Go to ISI>://000178662500069},
	author = {Ramachander, R. and Kim, C. A. and Phillips, M. L. and Mackereth, C. D. and Thanos, C. D. and McIntosh, L. P. and Bowie, J. U.}
}
@article {4405,
	title = {Structure of the Ets-1 pointed domain and mitogen-activated protein kinase phosphorylation site},
	journal = {Proceedings of the National Academy of Sciences of the United States of America},
	volume = {95},
	number = {21},
	year = {1998},
	note = {ISI Document Delivery No.: 129DLTimes Cited: 84Cited Reference Count: 37},
	month = {Oct},
	pages = {12129-12134},
	type = {Article},
	abstract = {The Pointed (PNT) domain and an adjacent mitogen-activated protein (MAP) kinase phosphorylation site are defined by sequence conservation among a subset of ets transcription factors and are implicated in two regulatory strategies, protein interactions and posttranslational modifications, respectively. By using NMR, we have determined the structure of a 110-residue fragment of murine Ets-1 that includes the PNT domain and MAP kinase site. The Ets-1 PNT domain forms a monomeric five-helix bundle. The architecture is distinct from that of any known DNA- or protein-binding module, including the helix-loop-helix fold proposed for the PNT domain of the ets protein TEL. The MAP kinase site is in a highly flexible region of both the unphosphorylated and phosphorylated forms of the Ets-1 fragment. Phosphorylation alters neither the structure nor monomeric state of the PNT domain. These results suggest that the Ets-1 PNT domain functions in heterotypic protein interactions and support the possibility that target recognition is coupled to structuring of the MAP kinase site.},
	keywords = {beta, CHRONIC MYELOMONOCYTIC LEUKEMIA, FUSION, GENE, NMR, OLIGOMERIZATION, TEL, TRANSCRIPTION FACTORS, TRANSLOCATION, TROPONIN-C},
	isbn = {0027-8424},
	url = {<Go to ISI>://000076447900013},
	author = {Slupsky, C. M. and Gentile, L. N. and Donaldson, L. W. and Mackereth, C. D. and Seidel, J. J. and Graves, B. J. and McIntosh, L. P.}
}
