Transcription regulation of ribosomal protein genes at different growth rates in continuous cultures of Kluyveromyces yeasts.
We have investigated the relationship between the growth rate of two Kluyveromyces strains that differ in their maximum growth rate, namely K. lactis (mumax = 0.5 h-1) and K. marxianus (mumax = 1.1 h-1), and the transcription rate of ribosomal protein (rp) genes in these strains. The growth rate of either strain was varied by culturing the cells in a chemostat under conditions of glucose limitation at different dilution rates. Although the steady-state levels of transcription of the rp-genes of both Kluyveromyces strains were tightly coupled to the cellular growth rate, no clear relationship between the level of rp-gene transcription and the amount of in vitro binding of the RAP1- and ABF1-like proteins to the promoters of these rp-genes was observed. Upon a sudden increase in the growth rate of a steady-state culture, the transcription of rp-genes of K. lactis showed a different response from that in K. marxianus. Whereas a substantial overexpression of the K. lactis rp-genes was found during at least 4-5 h, the level of expression of the K. marxianus rp-genes was almost immediately adjusted to the new growth rate.
Hoekstra
R
R
Department of Biochemistry and Molecular Biology, Vrije Universiteit Amsterdam, The Netherlands.
Groeneveld
P
P
Van Verseveld
H W
HW
Stouthamer
A H
AH
Planta
R J
RJ
D015152:Blotting, Northern; D015342:DNA Probes; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D005809:Genes, Regulator; D007716:Kluyveromyces / Q000235:genetics* / Q000254:growth & development; D010101:Oxygen Consumption; D012313:RNA / Q000032:analysis; D012097:Repressor Proteins / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D034501:Telomere-Binding Proteins; D014157:Transcription Factors
C061886:ABF1 protein, S cerevisiae; D015342:DNA Probes; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D012097:Repressor Proteins; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins; D034501:Telomere-Binding Proteins; D014157:Transcription Factors; C074461:RIF1 protein, S cerevisiae; D012313:RNA