TY  - JOUR
AU  - Kojić, Milorad
AU  - Zhou, QW
AU  - Lisby, M
AU  - Holloman, WK
PY  - 2006
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/256
AB  - Rec2 is the single Rad51 paralog in Ustilago maydis. Here, we find that Rec2 is required for radiation-induced Rad51 nuclear focus formation but that Rec2 foci form independently of Rad51 and Brh2. Brh2 foci also form in the absence of Rad51 and Rec2. By coprecipitation from cleared extracts prepared from Escherichia coli cells expressing the proteins, we found that Rec2 interacts physically not only with Rad51 and itself but also with Brh2. Transgenic expression of Brh2 in rec2 mutants can effectively restore radiation resistance, but the frequencies of spontaneous Rad51 focus formation and allelic recombination are elevated. The Dss1-independent Brh2-RPA70 fusion protein is also active in restoring radiation sensitivity of rec2 but is hyperactive to an extreme degree in allelic recombination and in suppressing the meiotic block of rec2. However, the high frequency of chromosome missegregation in meiotic products is an indicator of a corrupted process. The results demonstrate that the importance of Rec2 function is not only in stimulating recombination activity but also in ensuring that recombination is properly controlled.
PB  - Amer Soc Microbiology, Washington
T2  - Molecular and Cellular Biology
T1  - Rec2 interplay with both Brh2 and Rad51 balances recombinational repair in Ustilago maydis
EP  - 688
IS  - 2
SP  - 678
VL  - 26
DO  - 10.1128/MCB.26.2.678-688.2006
ER  - 

@article{
author = "Kojić, Milorad and Zhou, QW and Lisby, M and Holloman, WK",
year = "2006",
abstract = "Rec2 is the single Rad51 paralog in Ustilago maydis. Here, we find that Rec2 is required for radiation-induced Rad51 nuclear focus formation but that Rec2 foci form independently of Rad51 and Brh2. Brh2 foci also form in the absence of Rad51 and Rec2. By coprecipitation from cleared extracts prepared from Escherichia coli cells expressing the proteins, we found that Rec2 interacts physically not only with Rad51 and itself but also with Brh2. Transgenic expression of Brh2 in rec2 mutants can effectively restore radiation resistance, but the frequencies of spontaneous Rad51 focus formation and allelic recombination are elevated. The Dss1-independent Brh2-RPA70 fusion protein is also active in restoring radiation sensitivity of rec2 but is hyperactive to an extreme degree in allelic recombination and in suppressing the meiotic block of rec2. However, the high frequency of chromosome missegregation in meiotic products is an indicator of a corrupted process. The results demonstrate that the importance of Rec2 function is not only in stimulating recombination activity but also in ensuring that recombination is properly controlled.",
publisher = "Amer Soc Microbiology, Washington",
journal = "Molecular and Cellular Biology",
title = "Rec2 interplay with both Brh2 and Rad51 balances recombinational repair in Ustilago maydis",
pages = "688-678",
number = "2",
volume = "26",
doi = "10.1128/MCB.26.2.678-688.2006"
}

Kojić, M., Zhou, Q., Lisby, M.,& Holloman, W.. (2006). Rec2 interplay with both Brh2 and Rad51 balances recombinational repair in Ustilago maydis. in Molecular and Cellular Biology
Amer Soc Microbiology, Washington., 26(2), 678-688.
https://doi.org/10.1128/MCB.26.2.678-688.2006

Kojić M, Zhou Q, Lisby M, Holloman W. Rec2 interplay with both Brh2 and Rad51 balances recombinational repair in Ustilago maydis. in Molecular and Cellular Biology. 2006;26(2):678-688.
doi:10.1128/MCB.26.2.678-688.2006 .

Kojić, Milorad, Zhou, QW, Lisby, M, Holloman, WK, "Rec2 interplay with both Brh2 and Rad51 balances recombinational repair in Ustilago maydis" in Molecular and Cellular Biology, 26, no. 2 (2006):678-688,
https://doi.org/10.1128/MCB.26.2.678-688.2006 . .

TY  - JOUR
AU  - Kojić, Milorad
AU  - Zhou, QW
AU  - Lisby, M
AU  - Holloman, WK
PY  - 2005
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/235
AB  - Brh2, the BRCA2 homolog in Ustilago maydis, functions in recombinational repair of DNA damage by regulating Rad51 and is, in turn, regulated by Dss1. Dss1 is not required for Brh2 stability in vivo, nor for Brh2 to associate with Rad51, but is required for formation of green fluorescent protein (GFP)-Rad51 foci following DNA damage by gamma radiation. To understand more about the interplay between Brh2 and Dss1, we isolated mutant variants of Brh2 able to bypass the requirement for Dss1. These variants were found to lack the entire C-terminal DNA-Dss1 binding domain but to maintain the N-terminal region harboring the Rad51-interacting BRC element. GFP-Rad51 focus formation was nearly normal in brh2 mutant cells expressing a representative Brh2 variant with the C-terminal domain deleted. These findings suggest that the N-terminal region of Brh2 has an innate ability to organize Rad51. Survival after DNA damage was almost fully restored by a chimeric form of Brh2 having a DNA-binding domain from RPA70 fused to the Brh2 N-terminal domain, but Rad51 focus formation and mitotic recombination were elevated above wild-type levels. The results provide evidence for a mechanism in which Dss1 activates a Brh2-Rad51 complex and balances a finely regulated recombinational repair system.
PB  - Amer Soc Microbiology, Washington
T2  - Molecular and Cellular Biology
T1  - Brh2-dss1 interplay enables properly controlled recombination in Ustilago maydis
EP  - 2557
IS  - 7
SP  - 2547
VL  - 25
DO  - 10.1128/MCB.25.7.2547-2557.2005
ER  - 

@article{
author = "Kojić, Milorad and Zhou, QW and Lisby, M and Holloman, WK",
year = "2005",
abstract = "Brh2, the BRCA2 homolog in Ustilago maydis, functions in recombinational repair of DNA damage by regulating Rad51 and is, in turn, regulated by Dss1. Dss1 is not required for Brh2 stability in vivo, nor for Brh2 to associate with Rad51, but is required for formation of green fluorescent protein (GFP)-Rad51 foci following DNA damage by gamma radiation. To understand more about the interplay between Brh2 and Dss1, we isolated mutant variants of Brh2 able to bypass the requirement for Dss1. These variants were found to lack the entire C-terminal DNA-Dss1 binding domain but to maintain the N-terminal region harboring the Rad51-interacting BRC element. GFP-Rad51 focus formation was nearly normal in brh2 mutant cells expressing a representative Brh2 variant with the C-terminal domain deleted. These findings suggest that the N-terminal region of Brh2 has an innate ability to organize Rad51. Survival after DNA damage was almost fully restored by a chimeric form of Brh2 having a DNA-binding domain from RPA70 fused to the Brh2 N-terminal domain, but Rad51 focus formation and mitotic recombination were elevated above wild-type levels. The results provide evidence for a mechanism in which Dss1 activates a Brh2-Rad51 complex and balances a finely regulated recombinational repair system.",
publisher = "Amer Soc Microbiology, Washington",
journal = "Molecular and Cellular Biology",
title = "Brh2-dss1 interplay enables properly controlled recombination in Ustilago maydis",
pages = "2557-2547",
number = "7",
volume = "25",
doi = "10.1128/MCB.25.7.2547-2557.2005"
}

Kojić, M., Zhou, Q., Lisby, M.,& Holloman, W.. (2005). Brh2-dss1 interplay enables properly controlled recombination in Ustilago maydis. in Molecular and Cellular Biology
Amer Soc Microbiology, Washington., 25(7), 2547-2557.
https://doi.org/10.1128/MCB.25.7.2547-2557.2005

Kojić M, Zhou Q, Lisby M, Holloman W. Brh2-dss1 interplay enables properly controlled recombination in Ustilago maydis. in Molecular and Cellular Biology. 2005;25(7):2547-2557.
doi:10.1128/MCB.25.7.2547-2557.2005 .

Kojić, Milorad, Zhou, QW, Lisby, M, Holloman, WK, "Brh2-dss1 interplay enables properly controlled recombination in Ustilago maydis" in Molecular and Cellular Biology, 25, no. 7 (2005):2547-2557,
https://doi.org/10.1128/MCB.25.7.2547-2557.2005 . .

TY  - JOUR
AU  - Kojić, Milorad
AU  - Holloman, WK
PY  - 2004
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/198
AB  - The tumor suppressor BRCA2 plays an essential role in repair of double-strand DNA breaks by regulating the action of the RAD51 recombinase. The activity of BRCA2 in turn is governed by DSS1, a small acidic protein that appears to function as a necessary cofactor. A model fungal system that reproduces the BRCA2-RAD51 interaction offers the opportunity to understand at the molecular level the mechanism of DSS1 activation.
PB  - Taylor & Francis Inc, Philadelphia
T2  - Cell Cycle
T1  - BRCA2-RAD51-DSS1 interplay examined from a microbial perspective
EP  - 248
IS  - 3
SP  - 247
VL  - 3
DO  - 10.4161/cc.3.3.701
ER  - 

@article{
author = "Kojić, Milorad and Holloman, WK",
year = "2004",
abstract = "The tumor suppressor BRCA2 plays an essential role in repair of double-strand DNA breaks by regulating the action of the RAD51 recombinase. The activity of BRCA2 in turn is governed by DSS1, a small acidic protein that appears to function as a necessary cofactor. A model fungal system that reproduces the BRCA2-RAD51 interaction offers the opportunity to understand at the molecular level the mechanism of DSS1 activation.",
publisher = "Taylor & Francis Inc, Philadelphia",
journal = "Cell Cycle",
title = "BRCA2-RAD51-DSS1 interplay examined from a microbial perspective",
pages = "248-247",
number = "3",
volume = "3",
doi = "10.4161/cc.3.3.701"
}

Kojić, M.,& Holloman, W.. (2004). BRCA2-RAD51-DSS1 interplay examined from a microbial perspective. in Cell Cycle
Taylor & Francis Inc, Philadelphia., 3(3), 247-248.
https://doi.org/10.4161/cc.3.3.701

Kojić M, Holloman W. BRCA2-RAD51-DSS1 interplay examined from a microbial perspective. in Cell Cycle. 2004;3(3):247-248.
doi:10.4161/cc.3.3.701 .

Kojić, Milorad, Holloman, WK, "BRCA2-RAD51-DSS1 interplay examined from a microbial perspective" in Cell Cycle, 3, no. 3 (2004):247-248,
https://doi.org/10.4161/cc.3.3.701 . .

TY  - JOUR
AU  - Kojić, Milorad
AU  - Yang, HJ
AU  - Kostrub, CF
AU  - Pavletich, NP
AU  - Holloman, WK
PY  - 2003
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/186
AB  - DSS1 encodes a small acidic protein shown in recent structural studies to interact with the DNA binding domain of BRCA2. Here we report that an ortholog of DSS1 is present in Ustilago maydis and associates with Brh2, the BRCA2-related protein, thus recapitulating the protein partnership in this genetically amenable fungus. Mutants of U. maydis deleted of DSS1 are extremely radiation sensitive, deficient in recombination, defective in meiosis, and disturbed in genome stability; these phenotypes mirror previous observations of U. maydis mutants deficient in Brh2 or Rad51. These findings conclusively show that Dss1 constitutes a protein with a significant role in the recombinational repair pathway in U. maydis, and imply that it plays a similar key role in the recombination systems of organisms in which recombinational repair is BRCA2 dependent.
PB  - Cell Press, Cambridge
T2  - Molecular Cell
T1  - The BRCA2-interacting protein DSS1 is vital for DNA repair, recombination, and genome stability in Ustilago maydis
EP  - 1049
IS  - 4
SP  - 1043
VL  - 12
DO  - 10.1016/S1097-2765(03)00367-8
ER  - 

@article{
author = "Kojić, Milorad and Yang, HJ and Kostrub, CF and Pavletich, NP and Holloman, WK",
year = "2003",
abstract = "DSS1 encodes a small acidic protein shown in recent structural studies to interact with the DNA binding domain of BRCA2. Here we report that an ortholog of DSS1 is present in Ustilago maydis and associates with Brh2, the BRCA2-related protein, thus recapitulating the protein partnership in this genetically amenable fungus. Mutants of U. maydis deleted of DSS1 are extremely radiation sensitive, deficient in recombination, defective in meiosis, and disturbed in genome stability; these phenotypes mirror previous observations of U. maydis mutants deficient in Brh2 or Rad51. These findings conclusively show that Dss1 constitutes a protein with a significant role in the recombinational repair pathway in U. maydis, and imply that it plays a similar key role in the recombination systems of organisms in which recombinational repair is BRCA2 dependent.",
publisher = "Cell Press, Cambridge",
journal = "Molecular Cell",
title = "The BRCA2-interacting protein DSS1 is vital for DNA repair, recombination, and genome stability in Ustilago maydis",
pages = "1049-1043",
number = "4",
volume = "12",
doi = "10.1016/S1097-2765(03)00367-8"
}

Kojić, M., Yang, H., Kostrub, C., Pavletich, N.,& Holloman, W.. (2003). The BRCA2-interacting protein DSS1 is vital for DNA repair, recombination, and genome stability in Ustilago maydis. in Molecular Cell
Cell Press, Cambridge., 12(4), 1043-1049.
https://doi.org/10.1016/S1097-2765(03)00367-8

Kojić M, Yang H, Kostrub C, Pavletich N, Holloman W. The BRCA2-interacting protein DSS1 is vital for DNA repair, recombination, and genome stability in Ustilago maydis. in Molecular Cell. 2003;12(4):1043-1049.
doi:10.1016/S1097-2765(03)00367-8 .

Kojić, Milorad, Yang, HJ, Kostrub, CF, Pavletich, NP, Holloman, WK, "The BRCA2-interacting protein DSS1 is vital for DNA repair, recombination, and genome stability in Ustilago maydis" in Molecular Cell, 12, no. 4 (2003):1043-1049,
https://doi.org/10.1016/S1097-2765(03)00367-8 . .

TY  - JOUR
AU  - Kojić, Milorad
AU  - Kostrub, CF
AU  - Buchman, AR
AU  - Holloman, WK
PY  - 2002
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/163
AB  - In a screen for DNA repair-defective mutants in the fungus Ustilago maydis, a gene encoding a BRCA2 family member, designated here as Brh2, was identified. A brh2 null allele was found to be defective in allelic recombination, meiosis, and repair of gaps and ionizing radiation damage to the same extent as rad51. Frequent marker loss in meiosis and diploid formation suggested that genomic instability was associated with brh2. This notion was confirmed by molecular karyotype analysis, which revealed gross chromosomal alterations associated with brh2. Yeast two-hybrid analysis indicated interaction between Brh2 and Rad51. Recapitulation in U. maydis of defects in DNA repair and genome stability associated with brh2 means that the BRCA2 gene family is more widespread than previously thought.
PB  - Cell Press, Cambridge
T2  - Molecular Cell
T1  - BRCA2 homolog required for proficiency in DNA repair, recombination, and genome stability in Ustilago maydis
EP  - 691
IS  - 3
SP  - 683
VL  - 10
DO  - 10.1016/S1097-2765(02)00632-9
ER  - 

@article{
author = "Kojić, Milorad and Kostrub, CF and Buchman, AR and Holloman, WK",
year = "2002",
abstract = "In a screen for DNA repair-defective mutants in the fungus Ustilago maydis, a gene encoding a BRCA2 family member, designated here as Brh2, was identified. A brh2 null allele was found to be defective in allelic recombination, meiosis, and repair of gaps and ionizing radiation damage to the same extent as rad51. Frequent marker loss in meiosis and diploid formation suggested that genomic instability was associated with brh2. This notion was confirmed by molecular karyotype analysis, which revealed gross chromosomal alterations associated with brh2. Yeast two-hybrid analysis indicated interaction between Brh2 and Rad51. Recapitulation in U. maydis of defects in DNA repair and genome stability associated with brh2 means that the BRCA2 gene family is more widespread than previously thought.",
publisher = "Cell Press, Cambridge",
journal = "Molecular Cell",
title = "BRCA2 homolog required for proficiency in DNA repair, recombination, and genome stability in Ustilago maydis",
pages = "691-683",
number = "3",
volume = "10",
doi = "10.1016/S1097-2765(02)00632-9"
}

Kojić, M., Kostrub, C., Buchman, A.,& Holloman, W.. (2002). BRCA2 homolog required for proficiency in DNA repair, recombination, and genome stability in Ustilago maydis. in Molecular Cell
Cell Press, Cambridge., 10(3), 683-691.
https://doi.org/10.1016/S1097-2765(02)00632-9

Kojić M, Kostrub C, Buchman A, Holloman W. BRCA2 homolog required for proficiency in DNA repair, recombination, and genome stability in Ustilago maydis. in Molecular Cell. 2002;10(3):683-691.
doi:10.1016/S1097-2765(02)00632-9 .

Kojić, Milorad, Kostrub, CF, Buchman, AR, Holloman, WK, "BRCA2 homolog required for proficiency in DNA repair, recombination, and genome stability in Ustilago maydis" in Molecular Cell, 10, no. 3 (2002):683-691,
https://doi.org/10.1016/S1097-2765(02)00632-9 . .

TY  - JOUR
AU  - Kojić, Milorad
AU  - Thompson, CW
AU  - Holloman, WK
PY  - 2001
UR  - https://imagine.imgge.bg.ac.rs/handle/123456789/159
AB  - The REC2 gene of Ustilago maydis encodes a homologue of the Escherichia coli RecA protein and was first identified in a screen for UV-sensitive mutants. The original isolate, rec2-1, was found to be deficient in repair of DNA damage, genetic recombination and meiosis. We report here that the rec2-197 allele, which was constructed by gene disruption, retains some biological activity and is partially dominant with respect to REC2. The basis for the residual activity is probably as a result of expression of a diffusible product from the rec2-197 allele that augments or interferes with REC2 functions. This product appears to be a polypeptide expressed from a remnant of the 5' end of the open reading frame that was not removed in creating the gene disruption. The mutator activity and disturbed meiosis of rec2-197 suggest that the Rec2 protein functions in a process that avoids spontaneous mutation and insures faithful meiotic chromosome segregation. A prediction based on the phenotype of rec2-197 is that Rec2 protein interacts with one or more other proteins in directing these functions. To identify interacting proteins we performed a yeast two-hybrid screen and found Rad51 as a candidate. Rec2-197 and Rad51 appear to interact to a similar degree.
PB  - Blackwell Science Ltd, Oxford
T2  - Molecular Microbiology
T1  - Disruptions of the Ustilago maydis REC2 gene identify a protein domain important in directing recombinational repair of DNA
EP  - 1426
IS  - 6
SP  - 1415
VL  - 40
DO  - 10.1046/j.1365-2958.2001.02490.x
ER  - 

@article{
author = "Kojić, Milorad and Thompson, CW and Holloman, WK",
year = "2001",
abstract = "The REC2 gene of Ustilago maydis encodes a homologue of the Escherichia coli RecA protein and was first identified in a screen for UV-sensitive mutants. The original isolate, rec2-1, was found to be deficient in repair of DNA damage, genetic recombination and meiosis. We report here that the rec2-197 allele, which was constructed by gene disruption, retains some biological activity and is partially dominant with respect to REC2. The basis for the residual activity is probably as a result of expression of a diffusible product from the rec2-197 allele that augments or interferes with REC2 functions. This product appears to be a polypeptide expressed from a remnant of the 5' end of the open reading frame that was not removed in creating the gene disruption. The mutator activity and disturbed meiosis of rec2-197 suggest that the Rec2 protein functions in a process that avoids spontaneous mutation and insures faithful meiotic chromosome segregation. A prediction based on the phenotype of rec2-197 is that Rec2 protein interacts with one or more other proteins in directing these functions. To identify interacting proteins we performed a yeast two-hybrid screen and found Rad51 as a candidate. Rec2-197 and Rad51 appear to interact to a similar degree.",
publisher = "Blackwell Science Ltd, Oxford",
journal = "Molecular Microbiology",
title = "Disruptions of the Ustilago maydis REC2 gene identify a protein domain important in directing recombinational repair of DNA",
pages = "1426-1415",
number = "6",
volume = "40",
doi = "10.1046/j.1365-2958.2001.02490.x"
}

Kojić, M., Thompson, C.,& Holloman, W.. (2001). Disruptions of the Ustilago maydis REC2 gene identify a protein domain important in directing recombinational repair of DNA. in Molecular Microbiology
Blackwell Science Ltd, Oxford., 40(6), 1415-1426.
https://doi.org/10.1046/j.1365-2958.2001.02490.x

Kojić M, Thompson C, Holloman W. Disruptions of the Ustilago maydis REC2 gene identify a protein domain important in directing recombinational repair of DNA. in Molecular Microbiology. 2001;40(6):1415-1426.
doi:10.1046/j.1365-2958.2001.02490.x .

Kojić, Milorad, Thompson, CW, Holloman, WK, "Disruptions of the Ustilago maydis REC2 gene identify a protein domain important in directing recombinational repair of DNA" in Molecular Microbiology, 40, no. 6 (2001):1415-1426,
https://doi.org/10.1046/j.1365-2958.2001.02490.x . .