摘要:

AbstractThe transcription of the majority of the ribosomal protein (rp) genes ofSaccharmoyces cerevisiaeis activated bycis‐acting elements, designated RPG boxes, which specifically bind the multifunctional protein RAPIin vitro.To investigate to what extent this global system of tanscription regulation has been conserved, we have isolated a number of rp genes of the related yeast speciesKluyveromyces lactisandKluyveromyces marxianus, whose counterparts inSaccharomycesare controlled by RAPI. The coding regions of these genes showed a sequence similarity of about 90% when compared to theirSaccharomycescounterparts. In contrast, little or no sequence similarity was found between the upstream regions and the intervening sequences ofKluyveromycesandSaccharomyceshomologs. However, the occurrence and the position of the introns is conserved. The sequence data also show that the physical linkage that exists inS. cerevisiaebetween the rp genes encoding RP59 (CRY1), S24 and L46 is conserved inKluyveromyces. Northern analysis demonstrated that each of the isolatedKluyveromycesgenes is transcriptionally active.By sequence comparison we idetified a number of conseerved sequences in the upstream region of each of theKluyveromycesrp genes, which we designated the X, Z and RPGKboxes. The last one is highly similar, though not identical, to theS. cerevisiaeRPG box.Functional analysis of the intergenic region between the genes encodingKluyveromycesribosomal proteins S24 and L46 showed that the RPGKbox (+Z box) functions as a transcriptional activator, while the X box acts as a trascriptional repressor. Band‐shift assays confirmed the existence of a RAP1‐like protein inKluyveromycesthat binds to the RPGKbox but not to theS. cerevisiaeRPG box. In contrast,S. cerevisiaeRAP1 did recognize the RP

ISSN:0749-503X    

DOI:10.1002/yea.320081102

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractA technique is described for the isolation and purification of intact, respiratory‐competent mitochondria fromSachizo‐saccharomyces pombe. The purified mitochondria are capabel of oxidizing NADH and succinate as resporatory substrates. indicating the presence of succinate dehydorgenase and an NADH dehydrogenase located on the outer suface of the inner membrane. Mitochondria display good respiratory control with an ADP/O ratio of<2. Respiratory activity is linearly dependent upon the redox poise of the quinone pool, suggesting the presence of an unbranched repiratory pathway to molecular oxygen. Immunogold labelling using antisera raised against mitochodria proteins (SSPI, SSCI, and PHSPI) from three different species, namely S.pombe,Saccharomyces cerevisianeand the plantPisum sativumrespectively, has been used to investigate the presence and ultrastructure of the mitochondria isolated by this procedure. The immunocytochemistry was carried out using cells containing wild‐type levels of SSPI protein and cells over‐expressing the protein. These results also demonstrate the capacity of mitochondria to import increased levels of proteinin vivo.In vitroimport experiments using COXIV‐DHFR indicate that purifiedS. pombemitochondria can efficiently import this precursor, and that protein translocation is dependent upon an oxidizable substrate and a membrane

ISSN:0749-503X    

DOI:10.1002/yea.320081103

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractFactors influencing the direct transformation of the yeastSaccharomyces cerevisiaewith synthetic oligonucleotides were investigated by selecting forcyc1transformants that contained at least partially fuctional iso‐1‐cytochromec. Aproximately 3 × 104transformanrs, constituting 0·1% of the cells, were obtained by using 1 mg of oligonucleotide in the reaction mixture. Carrier, such as heterogenous oligonucleotides, enhanced transformation frequencies. Transformation frequencies were dramatically reduced if the oligonucleotides had a large number of mismatches or had terminally located mismatches. Transformation with oligonucleotides, but not with linearized double‐strand plasmid, was efficient in arad52−strain, ssuggesting that the pathway for transformation with oligonucleotides is different from that with linearized double‐strand plasmid. We describe a procedure of co‐transformation with two oligonucleotides, one correcting thecyc1defect of the target allele in the host strain, and the other producing a desired amono acid alteration elsewhere in the iso‐1‐cytochromecmolecule; approximately 20% of the transformants obtained by co‐transformation contained these desired

ISSN:0749-503X    

DOI:10.1002/yea.320081104

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractThe abundant multifuctional protein ABF1 ofSaccharomyces cerevisiaebinds to the upstream region of several genes, including some ribosomal protein genes like the one encoding protein S33. Deletion of th ABF1‐binding sequence lowers the transcription of these genes three‐ to more than ten‐fold.We have isolated the S33 genes of two related yeast species.Kluyveromyces lactisandKluveromyces marxianus. Comparison of the nucleotide sequences of these S33 genes with their counterpart formS. Cerevisiaeshows a strong sequence similarity covering the whole of the coding regions. In contrast, little or no sequence similarly is found in the 5′‐flanking regions of the three genes. Also the trailer regions differ considerably in both length and sequence from one species to another.An ABF1‐binding site is present in the upstream region of the S33 gene ofK. marxianus. Retardation analyses showed that this sequences is able to bind a protein present inKluyveromycescells with a molecular mass somewhat lower than that ofS. cerevisiaeABF1. Functional analyses, using a β‐glucuronidase reporter system, showed that the ABF1‐binding site is indeed involved in transcription activation of theK. marxianusS33 gene inKluyveromycesDNA and Northern blots did not show a signal.These results indicate thatS. cerevisiaeandKluyveromycescontain functionally related but structurally dissimilar AB

ISSN:0749-503X    

DOI:10.1002/yea.320081105

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractIn the course of our studies on the molecular mechanisms involved in peroxisome biogenesis, we have isolated several mutants of the methylotrophic yeastHansenula polymorphaimpaired in the import of peroximal matrix proteins. These mutants are characterized by the presence of small intact peroxisomes, while the bulk of the peroxisomal matrix protein is not imported and resides in the cytosol (Pim−phenotype). Genetic analysis of back‐crossed mutants revealed five different complementation groups, which were designatedPERI–PER5. Mapping studies to determine the linkage relationships indicated that the observed Pim−phenotypes were determined by single recessive nuclear mutations.The different mutants had comparable phenotypes: (i) they were impaired to utilize methanol as the sole source of carbon and energy but grew well on various other compounds, including nitrogen sources, the metabolism of which is known to be mediated by peroxisome‐borne enzymes in wild‐type cells; (ii) all peroxisomal enzymes tested were induced, assembled and activated as in wild‐type cells although their activities varied between the different representative mutants; (iii) all peroxisomal proteins, whether constitutive or inducible, were found both in the cytosol and in the small peroxisomes. These results suggest that a general, major import mechanism is affected i

ISSN:0749-503X    

DOI:10.1002/yea.320081106

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractAn ‘electroinic’ gene mapping procedure based on computer‐aided search for overlapping gene sequences was used to identify adjacent genes and localize several putative RNA helicase genes to different chromosomes.PRP28andAMD1genes map to the right arm of chromosome IV netxt tosup2, which encodes a tyrsine tRNAPRP16, previouslymapped to chromosome XI, is tightly linked toMRP−L20.PRP22is adjacent toPRE1, whose chromosomal location is currently unknown. The utility of this aproach in yeast gene mapping is ev

ISSN:0749-503X    

DOI:10.1002/yea.320081107

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractWe report the sequence of a 12 299 bp DNA fragment from the left arm ofSaccharomyces cerevisiaechromosome XI. This fragment is located between the genetic locimif2andmak11. We have detected five new open reading frames (ORFs) longer than 300 bp provisionally calledYKL248toYKL252. One of them,YKL248encodes a homolog of the UDP‐glucose pyrophosphorylase from potato. The product ofYKL251contains the consensus for zinc binding proteins, similar to those of a number of fungal transcriptional activators. The three other ORFs do not show significant homology to known protei

ISSN:0749-503X    

DOI:10.1002/yea.320081108

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractWe report the wequence of a 9·3 kb DNA segment of chromosome XI ofSaccharomyces cerevisiae, located between theMAK11locus and the centromere. This sequence contains four long open reading frames (ORFs). YKL160, YKL162, YKL164, YKL165 and part of another ORF, YKL166, covering altogether 90% of the entire sequence. One of these ORFs YKL164, corresponds toCCE1. Translation products of two other ORFs, YKL160 and YKL165, exhibit homology with previously knownS. cerevisiaeproetins: the robosomal protein L10, and theMYO2gene product, respectively

ISSN:0749-503X    

DOI:10.1002/yea.320081109

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

ISSN:0749-503X    

DOI:10.1002/yea.320081101

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY