. 13: 489–490 (1997)

The RAD29 Gene: Map Position on the Right Arm ofChromosome II

SERGUEY A. KOZHIN*, TATIANA N. KOZHINA AND VLADIMIR G. KOROLEV

Department of Molecular and Radiation Biophysics, Petersburg Nuclear Physics Institute, Russian Academy ofScience, Gatchina, Leningrad distr., 188350, Russia

Received 2 April 1996; accepted 22 October 1996

Yeast 13: 489–490, 1997.No. of Figures: 0. No. of Tables: 1. No. of References: 4.

— Saccharomyces cerevisiae; genetic analysis; repair and recombination genes; RAD29; mapping.

INTRODUCTION

In this communication, we present data that deter-mine the map position of RAD29–a new geneinvolved in DNA repair. The mutant of this genewas selected as showing a hyper-UV-sensitivephenotype in a rad2 genetic background. Thisrecessive mutation has a pleiotropic phenotype:sensitivity to UV-light, methyl methanesulfonate(MMS), nitrous acid and gamma-rays (onlydiploid cells in the latter case). Because the allelismtests demonstrated that this mutation is not allelicto any of the known rad mutations having MMSsensitivity (including xrs2, rad50–rad58, srs2, rad6,rad18 and apn1), we propose to designate thismutation as rad29-l and, correspondingly, the newgene which it defines as RAD29. Complete infor-mation for this gene will be published in the future(S. A. Kozhin et al., in preparation). In the presentstudy, we have mapped the RAD29 gene inrelation to LYS2, PHO3 and CEN2.

RESULTS

A diploid strain from our stock collection ofSaccharomyces cerevisiae was used in the tetradanalysis to map RAD29 in relation to PHO3,LYS2 and CEN2: D3300 (MATá lys2-A12 leu2-3,

112 trp1 rad29-1/MATa pho3-93 his7-1). Themedia, methods for cell cultivation and tetradanalysis were all as described previously(Zakharov et al., 1984).By employing the method of chromosome

destabilization (Falco and Bostian, 1983) in pre-liminary experiments, we found that the RAD29gene is located on the right arm of chromosome II(data not presented). In Table 1, we present themapping data obtained by tetrad analysis of thediploid D3300. From this table, one can see that

*Correspondence to: Serguey A, Kozhin.Contract grant sponsor: Russian Fund of FundamentalResearch.Contract grant sponsor: State program ‘Priority of GeneticsInitiative’.

Table 1. Tetrad segregation in the diploid D3300.

Investigatedgenes

Tetrad segregation Map distance (cM)

PD NPD T Xp* XD†

RAD29–PHO3 38 0 13 12·7 12·5RAD29–LYS2 27 0 24 23·5 23·6PHO3–LYS2 36 0 15 14·7 14·5RAD29–TRP1 8 7 35 35·0‡ 36·0‡

*Xp, calculated by the method of Perkins (1949).†XD, calculated by the method of Ma and Mortimer (1983).‡These values reflect the distance between RAD29 and CEN2.

Figure 1. Map position of investigated genes on the right armof chromosome II.

CCC 0749–503X/97/050489–02 $17.50? 1997 by John Wiley & Sons Ltd

the RAD29 gene is linked to PHO3 (the mapdistance between these genes is 12.5 cM) and toLYS2 (23.6 cM). To map the RAD29 gene inrelation to CEN2 we used TRP1–a gene closelylinked to CEN4 (0.45 cM). In this case, the mapdistance of RAD29 from CEN2 may be calculatedas 0.5 ft RAD29–TRP1 because the second-division segregation frequency for TRP1 ispractically zero.Thus, the order of the investigated genes on the

right arm of chromosome II is as presented inFigure 1.

ACKNOWLEDGEMENTS

This work was supported by grants from theRussian Fund of Fundamental Research and theState Program ‘Priority of Genetics Initiative’.

REFERENCES

Falco, S. A. and Botstein, D. A. (1983). A rapidchromosome mapping method for cloned fragmentsof yeast DNA. Genetics 105, 857–872.

Ma, C. and Mortimer, R. K. (1983). Empirical equationthat can be used to determine genetic map distancesfrom tetrad data. Mol. Cell. Biol. 3, 1886–1887.

Perkins, D. D. (1949). Biochemical mutants of the smutfungus Ustilago maydis. Genetics 34, 607–626.

Zakharov, I. A., Kozhin, S. A., Kozhina, T. A. andFedorova, I. V. (1984). Methods in Yeast Saccharo-myces cerevisiae genetics. Nauka, Leningrad.

490 . . .