M(3)S32 and M(3)86D correspond to RpS25. - Cook, K. (2006)
Subject: M(3)S32 and M(3)86D correspond to RpS25 M(3)S32 and M(3)86D correspond to RpS25 Kevin Cook Bloomington Stock Center, Indiana University I mapped the M(3)S32[1] mutation from Bloomington stock 537 by first crossing it to a stock carrying the ru[1] h[1] th[1] st[1] cu[1] sr[1] e[s] ca[1] chromosome, then backcrossing female progeny to the same stock and scoring rates of recombination between the Minute phenotype and the other markers. In these crosses, I found that the M(3)S32[1] chromosome failed to complement cu[1]. The Minute phenotype mapped between st and sr. Since Df(3R)M86D (86D1-2;86D3-4) deletes the Minute M(3)86D and cu, I suspected that M(3)S32[1] might also be a deletion in the same region. I found that M(3)S32[1] was lethal in combination with Df(3R)ED5506 (86C7;86D5), Df(3R)Exel6159 (86C3;86C7), Df(3R)ED5514 (86C7;86E11) or Df(3R)ED5518 (86C7;86E13). Only Df(3R)ED5514 and Df(3R)ED5518 delete ribosomal protein genes, the only class of genes demonstrated to correspond to Minutes. The other two deletions occupy more proximal positions. This again suggested M(3)S32[1] might be a deletion. My polytene chromosome squashes showed that the M(3)S32[1] chromosome carries a deletion of 86C8-13;86D8-E1 (the 86C7,8 doublet was present, 86C13 was absent, 86D8 was absent and the 86E1,2 doublet was present). Consequently, the M(3)S32[1] mutation should be renamed to indicate that it is a deletion. I suggest the name Df(3R)MS32. Df(3R)MS32 complemented pros[10409], pros[17], Df(3R)Exel9018 (86E2;86E4), Df(3R)Exel7308 (86E1;86E8) and Df(3R)ED5516 (86D8;86E13). These observations demonstrated that the deletion certainly ends proximal to pros, but likely ends even farther proximally. Df(3R)MS32 complemented the PXPnocturnin[d05983] and PEPgy2Tctp[EY09182] insertion chromosomes, indicating that the recessive lethality of these chromosomes is unrelated to these insertions. Df(3R)ED5514 and Df(3R)ED5518 delete the closely-linked ribosomal protein genes RpS25 and RpL3 (release 4 predicted position 86D8). The cytology of Df(3R)MS32 is consistent with it deleting these genes as well. Since the PSupor-PRpL3[KG05440] insertion disrupts an exon common to all RpL3 transcripts (as shown on GBrowse) and the intronic PBacRBe03180 insertion fails to complement PSupor-PRpL3[KG05440], both mutations disrupt RpL3 function. Neither insertion shows a Minute phenotype. This indicates that the most likely candidate for the Minute locus in this chromosomal region is RpS25. Consequently, both M(3)86D and M(3)S32 should be considered synonyms for RpS25.