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1.
Nat Genet ; 21(1 Suppl): 33-7, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9915498

RESUMO

Thousands of genes are being discovered for the first time by sequencing the genomes of model organisms, an exhilarating reminder that much of the natural world remains to be explored at the molecular level. DNA microarrays provide a natural vehicle for this exploration. The model organisms are the first for which comprehensive genome-wide surveys of gene expression patterns or function are possible. The results can be viewed as maps that reflect the order and logic of the genetic program, rather than the physical order of genes on chromosomes. Exploration of the genome using DNA microarrays and other genome-scale technologies should narrow the gap in our knowledge of gene function and molecular biology between the currently-favoured model organisms and other species.


Assuntos
Sondas de DNA , Genoma , Técnicas de Sonda Molecular , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Animais , Mapeamento Cromossômico , Bases de Dados Factuais , Expressão Gênica , Humanos , Técnicas de Sonda Molecular/economia , Análise de Sequência com Séries de Oligonucleotídeos/economia , Análise de Sequência de DNA
2.
Nat Genet ; 25(1): 58-62, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10802657

RESUMO

Membrane-associated and secreted proteins are an important class of proteins and include receptors, transporters, adhesion molecules, hormones and cytokines. Although algorithms have been developed to recognize potential amino-terminal membrane-targeting signals or transmembrane domains in protein sequences, their accuracy is limited and they require knowledge of the entire coding sequence, including the N terminus, which is not currently available for most of the genes in most organisms, including human. Several experimental approaches for identifying secreted and membrane proteins have been described, but none have taken a comprehensive genomic approach. Furthermore, none of these methods allow easy classification of clones from arrayed cDNA libraries, for which large-scale gene-expression data are now becoming available through the use of DNA microarrays. We describe here a rapid and efficient method for identifying genes that encode secreted or membrane proteins. mRNA species bound to membrane-associated polysomes were separated from other mRNAs by sedimentation equilibrium or sedimentation velocity. The distribution of individual transcripts in the 'membrane-bound' and 'cytosolic' fractions was quantitated for thousands of genes by hybridization to DNA microarrays. Transcripts known to encode secreted or membrane proteins were enriched in the membrane-bound fractions, whereas those known to encode cytoplasmic proteins were enriched in the fractions containing mRNAs associated with free and cytoplasmic ribosomes. On this basis, we identified over 275 human genes and 285 yeast genes that are likely to encode previously unrecognized secreted or membrane proteins.


Assuntos
Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Carbocianinas , Membrana Celular/química , Membrana Celular/genética , Membrana Celular/metabolismo , Humanos , Células Jurkat , Proteínas de Membrana/análise , Proteínas Nucleares/análise , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Hibridização de Ácido Nucleico , Saccharomyces cerevisiae , Frações Subcelulares/química , Frações Subcelulares/metabolismo
3.
Nat Genet ; 28(4): 327-34, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11455386

RESUMO

We determined the distribution of repressor-activator protein 1 (Rap1) and the accessory silencing proteins Sir2, Sir3 and Sir4 in vivo on the entire yeast genome, at a resolution of 2 kb. Rap1 is central to the cellular economy during rapid growth, targeting 294 loci, about 5% of yeast genes, and participating in the activation of 37% of all RNA polymerase II initiation events in exponentially growing cells. Although the DNA sequence recognized by Rap1 is found in both coding and intergenic sequences, the binding of Rap1 to the genome was highly specific to intergenic regions with the potential to act as promoters. This global phenomenon, which may be a general characteristic of sequence-specific transcriptional factors, indicates the existence of a genome-wide molecular mechanism for marking promoter regions.


Assuntos
Proteínas de Ligação a DNA/metabolismo , DNA/metabolismo , Genoma Fúngico , Mapeamento Físico do Cromossomo/métodos , Regiões Promotoras Genéticas/fisiologia , Saccharomyces cerevisiae/genética , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae , Sítios de Ligação/genética , DNA Intergênico/metabolismo , Proteínas Fúngicas/metabolismo , Regulação da Expressão Gênica/fisiologia , Genes Fúngicos/fisiologia , Glicólise/genética , Histona Desacetilases/metabolismo , Fases de Leitura Aberta/fisiologia , Ligação Proteica/fisiologia , RNA Polimerase II/metabolismo , Proteínas Ribossômicas/genética , Saccharomyces cerevisiae/metabolismo , Sirtuína 2 , Sirtuínas , Telômero/metabolismo , Transativadores/metabolismo
4.
Nat Genet ; 23(1): 41-6, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10471496

RESUMO

Gene amplifications and deletions frequently contribute to tumorigenesis. Characterization of these DNA copy-number changes is important for both the basic understanding of cancer and its diagnosis. Comparative genomic hybridization (CGH) was developed to survey DNA copy-number variations across a whole genome. With CGH, differentially labelled test and reference genomic DNAs are co-hybridized to normal metaphase chromosomes, and fluorescence ratios along the length of chromosomes provide a cytogenetic representation of DNA copy-number variation. CGH, however, has a limited ( approximately 20 Mb) mapping resolution, and higher-resolution techniques, such as fluorescence in situ hybridization (FISH), are prohibitively labour-intensive on a genomic scale. Array-based CGH, in which fluorescence ratios at arrayed DNA elements provide a locus-by-locus measure of DNA copy-number variation, represents another means of achieving increased mapping resolution. Published array CGH methods have relied on large genomic clone (for example BAC) array targets and have covered only a small fraction of the human genome. cDNAs representing over 30,000 radiation-hybrid (RH)-mapped human genes provide an alternative and readily available genomic resource for mapping DNA copy-number changes. Although cDNA microarrays have been used extensively to characterize variation in human gene expression, human genomic DNA is a far more complex mixture than the mRNA representation of human cells. Therefore, analysis of DNA copy-number variation using cDNA microarrays would require a sensitivity of detection an order of magnitude greater than has been routinely reported. We describe here a cDNA microarray-based CGH method, and its application to DNA copy-number variation analysis in breast cancer cell lines and tumours. Using this assay, we were able to identify gene amplifications and deletions genome-wide and with high resolution, and compare alterations in DNA copy number and gene expression.


Assuntos
DNA Complementar/análise , Dosagem de Genes , Genoma , Análise de Sequência de DNA/métodos , Cromossomos Humanos Par 17 , Feminino , Biblioteca Gênica , Genes erbB-2/genética , Genoma Humano , Humanos , Leucócitos/metabolismo , Masculino , Microscopia/métodos , Hibridização de Ácido Nucleico/métodos , Mapeamento Físico do Cromossomo , Análise de Sequência de DNA/instrumentação , Células Tumorais Cultivadas , Cromossomo X
5.
Nat Genet ; 24(3): 227-35, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10700174

RESUMO

We used cDNA microarrays to explore the variation in expression of approximately 8,000 unique genes among the 60 cell lines used in the National Cancer Institute's screen for anti-cancer drugs. Classification of the cell lines based solely on the observed patterns of gene expression revealed a correspondence to the ostensible origins of the tumours from which the cell lines were derived. The consistent relationship between the gene expression patterns and the tissue of origin allowed us to recognize outliers whose previous classification appeared incorrect. Specific features of the gene expression patterns appeared to be related to physiological properties of the cell lines, such as their doubling time in culture, drug metabolism or the interferon response. Comparison of gene expression patterns in the cell lines to those observed in normal breast tissue or in breast tumour specimens revealed features of the expression patterns in the tumours that had recognizable counterparts in specific cell lines, reflecting the tumour, stromal and inflammatory components of the tumour tissue. These results provided a novel molecular characterization of this important group of human cell lines and their relationships to tumours in vivo.


Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Análise de Sequência com Séries de Oligonucleotídeos , Células Tumorais Cultivadas/metabolismo , Mama/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Análise por Conglomerados , DNA Complementar/genética , Etiquetas de Sequências Expressas , Feminino , Humanos , Leucemia/genética , Leucemia/metabolismo , Leucemia/patologia , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Especificidade de Órgãos , Células Tumorais Cultivadas/classificação , Células Tumorais Cultivadas/efeitos dos fármacos
6.
Nat Genet ; 24(3): 236-44, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10700175

RESUMO

We used cDNA microarrays to assess gene expression profiles in 60 human cancer cell lines used in a drug discovery screen by the National Cancer Institute. Using these data, we linked bioinformatics and chemoinformatics by correlating gene expression and drug activity patterns in the NCI60 lines. Clustering the cell lines on the basis of gene expression yielded relationships very different from those obtained by clustering the cell lines on the basis of their response to drugs. Gene-drug relationships for the clinical agents 5-fluorouracil and L-asparaginase exemplify how variations in the transcript levels of particular genes relate to mechanisms of drug sensitivity and resistance. This is the first study to integrate large databases on gene expression and molecular pharmacology.


Assuntos
Antineoplásicos/farmacologia , DNA Complementar/genética , Bases de Dados Factuais , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Análise de Sequência com Séries de Oligonucleotídeos , Células Tumorais Cultivadas/metabolismo , Antineoplásicos/classificação , Análise por Conglomerados , DNA de Neoplasias/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Especificidade de Órgãos , Células Tumorais Cultivadas/classificação
7.
J Exp Med ; 194(11): 1639-47, 2001 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-11733578

RESUMO

The most common human leukemia is B cell chronic lymphocytic leukemia (CLL), a malignancy of mature B cells with a characteristic clinical presentation but a variable clinical course. The rearranged immunoglobulin (Ig) genes of CLL cells may be either germ-line in sequence or somatically mutated. Lack of Ig mutations defined a distinctly worse prognostic group of CLL patients raising the possibility that CLL comprises two distinct diseases. Using genomic-scale gene expression profiling, we show that CLL is characterized by a common gene expression "signature," irrespective of Ig mutational status, suggesting that CLL cases share a common mechanism of transformation and/or cell of origin. Nonetheless, the expression of hundreds of other genes correlated with the Ig mutational status, including many genes that are modulated in expression during mitogenic B cell receptor signaling. These genes were used to build a CLL subtype predictor that may help in the clinical classification of patients with this disease.


Assuntos
Expressão Gênica , Imunoglobulinas/genética , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Genótipo , Humanos , Imunofenotipagem
8.
J Cell Biol ; 107(6 Pt 2): 2551-61, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3060468

RESUMO

Three yeast actin-binding proteins were identified using yeast actin filaments as an affinity matrix. One protein appears to be a yeast myosin heavy chain; it is dissociated from actin filaments by ATP, it is similar in size (200 kD) to other myosins, and antibodies directed against Dictyostelium myosin heavy chain bind to it. Immunofluorescence experiments show that a second actin-binding protein (67 kD) colocalizes in vivo with both cytoplasmic actin cables and cortical actin patches, the only identifiable actin structures in yeast. The cortical actin patches are concentrated at growing surfaces of the yeast cell where they might play a role in membrane and cell wall insertion, and the third actin-binding protein (85 kD) is only detected in association with these structures. This 85-kD protein is therefore a candidate for a determinant of growth sites. The in vivo role of this protein was tested by overproduction; this overproduction causes a reorganization of the actin cytoskeleton which in turn dramatically affects the budding pattern and spatial growth organization of the yeast cell.


Assuntos
Actinas/metabolismo , Proteínas dos Microfilamentos/farmacologia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Autorradiografia , Eletroforese em Gel de Poliacrilamida , Imunofluorescência , Immunoblotting , Proteínas dos Microfilamentos/análise , Morfogênese , Miosinas/análise , Miosinas/fisiologia , Saccharomyces cerevisiae/análise
9.
J Cell Biol ; 106(6): 1997-2010, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3290223

RESUMO

We have used in vitro mutagenesis and gene replacement to construct five new cold-sensitive mutations in TUB2, the sole gene encoding beta-tubulin in the yeast Saccharomyces cerevisiae. These and one previously isolated tub2 mutant display diverse phenotypes that have allowed us to define the functions of yeast microtubules in vivo. At the restrictive temperature, all of the tub2 mutations inhibit chromosome segregation and block the mitotic cell cycle. However, different microtubule arrays are present in these arrested cells depending on the tub2 allele. One mutant (tub2-401) contains no detectable microtubules, two (tub2-403 and tub2-405) contain greatly diminished levels of both nuclear and cytoplasmic microtubules, one (tub2-104) contains predominantly nuclear microtubules, one (tub2-402) contains predominantly cytoplasmic microtubules, and one (tub2-404) contains prominent nuclear and cytoplasmic microtubule arrays. Using these mutants we demonstrate here that cytoplasmic microtubules are necessary for nuclear migration during the mitotic cell cycle and for nuclear migration and fusion during conjugation; only those mutants that possess cytoplasmic microtubules are able to perform these functions. We also show that microtubules are not required for secretory vesicle transport in yeast; bud growth and invertase secretion occur in cells which contain no microtubules.


Assuntos
Ciclo Celular , Microtúbulos/fisiologia , Tubulina (Proteína)/genética , Sequência de Aminoácidos , Benomilo/farmacologia , Núcleo Celular/fisiologia , Cromossomos/fisiologia , Temperatura Baixa , Conjugação Genética , Grânulos Citoplasmáticos/fisiologia , Citoesqueleto/fisiologia , Análise Mutacional de DNA , Meiose , Mitose , Dados de Sequência Molecular , Movimento , Recombinação Genética , Saccharomyces cerevisiae , Esporos Fúngicos/fisiologia , Relação Estrutura-Atividade
10.
J Cell Biol ; 114(3): 443-53, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1860879

RESUMO

Yeast mutants of cell cycle gene cdc48-1 arrest as large budded cells with microtubules spreading aberrantly throughout the cytoplasm from a single spindle plaque. The gene was cloned and disruption proved it to be essential. The CDC48 sequence encodes a protein of 92 kD that has an internal duplication of 200 amino acids and includes a nucleotide binding consensus sequence. Vertebrate VCP has a 70% identity over the entire length of the protein. Yeast Sec18p and mammalian N-ethylmaleimide-sensitive fusion protein, which are involved in intracellular transport, yeast Pas1p, which is essential for peroxisome assembly, and mammalian TBP-1, which influences HIV gene expression, are 40% identical in the duplicated region. Antibodies against CDC48 recognize a yeast protein of apparently 115 kD and a mammalian protein of 100 kD. Both proteins are bound loosely to components of the microsomal fraction as described for Sec18p and N-ethylmaleimide-sensitive fusion protein. This similarity suggests that CDC48p participates in a cell cycle function related to that of N-ethylmaleimide-sensitive fusion protein/Sec18p in Golgi transport.


Assuntos
Proteínas de Ciclo Celular/genética , Ciclo Celular , Proteínas Fúngicas/genética , Microcorpos/metabolismo , Saccharomyces cerevisiae/genética , Adenosina Trifosfatases , Sequência de Aminoácidos , Sequência de Bases , Western Blotting , Clonagem Molecular , DNA Fúngico , Proteínas Fúngicas/imunologia , Proteínas Fúngicas/metabolismo , Expressão Gênica , Histocitoquímica , Dados de Sequência Molecular , Família Multigênica , Mutação , Mapeamento por Restrição , Proteínas de Saccharomyces cerevisiae , Alinhamento de Sequência , Proteína com Valosina
11.
J Cell Biol ; 125(2): 381-91, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8163554

RESUMO

We characterized the yeast actin cytoskeleton at the ultrastructural level using immunoelectron microscopy. Anti-actin antibodies primarily labeled dense, patchlike cortical structures and cytoplasmic cables. This localization recapitulates results obtained with immunofluorescence light microscopy, but at much higher resolution. Immuno-EM double-labeling experiments were conducted with antibodies to actin together with antibodies to the actin binding proteins Abp1p and cofilin. As expected from immunofluorescence experiments, Abp1p, cofilin, and actin colocalized in immuno-EM to the dense patchlike structures but not to the cables. In this way, we can unambiguously identify the patches as the cortical actin cytoskeleton. The cortical actin patches were observed to be associated with the cell surface via an invagination of plasma membrane. This novel cortical cytoskeleton-plasma membrane interface appears to consist of a fingerlike invagination of plasma membrane around which actin filaments and actin binding proteins are organized. We propose a possible role for this unique cortical structure in wall growth and osmotic regulation.


Assuntos
Actinas/ultraestrutura , Membrana Celular/ultraestrutura , Citoesqueleto/ultraestrutura , Saccharomyces cerevisiae/ultraestrutura , Actinas/metabolismo , Ciclo Celular , Membrana Celular/metabolismo , Endocitose , Proteínas dos Microfilamentos/metabolismo , Microscopia de Fluorescência , Microscopia Imunoeletrônica , Osmose , Saccharomyces cerevisiae/metabolismo
12.
J Cell Biol ; 122(4): 743-51, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8349727

RESUMO

The spindle pole body (SPB) of Saccharomyces cerevisiae serves as the centrosome in this organism, undergoing duplication early in the cell cycle to generate the two poles of the mitotic spindle. The conditional lethal mutation ndc1-1 has previously been shown to cause asymmetric segregation, wherein all the chromosomes go to one pole of the mitotic spindle (Thomas, J. H., and D. Botstein. 1986. Cell. 44:65-76). Examination by electron microscopy of mutant cells subjected to the nonpermissive temperature reveals a defect in SPB duplication. Although duplication is seen to occur, the nascent SPB fails to undergo insertion into the nuclear envelope. The parental SPB remains functional, organizing a monopolar spindle to which all the chromosomes are presumably attached. Order-of-function experiments reveal that the NDC1 function is required in G1 after alpha-factor arrest but before the arrest caused by cdc34. Molecular analysis shows that the NDC1 gene is essential and that it encodes a 656 amino acid protein (74 kD) with six or seven putative transmembrane domains. This evidence for membrane association is further supported by immunofluorescent localization of the NDC1 product to the vicinity of the nuclear envelope. These findings suggest that the NDC1 protein acts within the nuclear envelope to mediate insertion of the nascent SPB.


Assuntos
Proteínas Fúngicas/metabolismo , Genes Fúngicos , Proteínas de Membrana/genética , Membrana Nuclear/ultraestrutura , Proteínas Nucleares/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Fuso Acromático/ultraestrutura , Sequência de Aminoácidos , Sequência de Bases , Imunofluorescência , Teste de Complementação Genética , Dados de Sequência Molecular , Mutagênese Insercional , Complexo de Proteínas Formadoras de Poros Nucleares , Mapeamento por Restrição
13.
Science ; 240(4858): 1439-43, 1988 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-3287619

RESUMO

The yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe have become popular and successful model systems for understanding eukaryotic biology at the cellular and molecular levels. The reasons for this success are experimental tractability, especially in applying classical and molecular genetic methods to associate genes with proteins and functions within the cell.


Assuntos
Projetos de Pesquisa , Saccharomyces cerevisiae , Modelos Biológicos , Modelos Genéticos , Recombinação Genética , Saccharomyces cerevisiae/genética
14.
Science ; 236(4808): 1567-70, 1987 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-2884728

RESUMO

An efficient strategy for mapping human genes that cause recessive traits has been devised that uses mapped restriction fragment length polymorphisms (RFLPs) and the DNA of affected children from consanguineous marriages. The method involves detection of the disease locus by virtue of the fact that the adjacent region will preferentially be homozygous by descent in such inbred children. A single affected child of a first-cousin marriage is shown to contain the same total information about linkage as a nuclear family with three affected children. Calculations show that it should be practical to map a recessive disease gene by studying DNA from fewer than a dozen unrelated, affected inbred children, given a complete RFLP linkage map. The method should make it possible to map many recessive diseases for which it is impractical or impossible to collect adequate numbers of families with multiple affected offspring.


Assuntos
Mapeamento Cromossômico , Consanguinidade , DNA/genética , Genes Recessivos , Doenças Genéticas Inatas/genética , Mapeamento Cromossômico/métodos , Ligação Genética , Homozigoto , Linhagem , Polimorfismo de Fragmento de Restrição
15.
Science ; 263(5149): 963-6, 1994 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-8310294

RESUMO

Calmodulin, a cytoplasmic calcium-binding protein, is indispensable for eukaryotic cell growth. Examination of 14 temperature-sensitive yeast mutants bearing one or more phenylalanine to alanine substitutions in the single essential calmodulin gene of yeast (CMD1) revealed diverse essential functions. Mutations could be classified into four intragenic complementation groups. Each group showed different characteristic functional defects in actin organization, calmodulin localization, nuclear division, or bud emergence. Phenylalanine residues implicated in calmodulin localization and nuclear division are located in the amino-terminal half of the protein, whereas those implicated in actin organization and bud emergence are located in the carboxyl-terminal half.


Assuntos
Calmodulina/fisiologia , Saccharomyces cerevisiae/fisiologia , Actinas/ultraestrutura , Calmodulina/química , Calmodulina/genética , Ciclo Celular , Replicação do DNA , Genes Fúngicos , Teste de Complementação Genética , Mutagênese Sítio-Dirigida , Mutação , Fenótipo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/ultraestrutura , Temperatura
16.
Science ; 217(4557): 371-3, 1982 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-7046050

RESUMO

A mutant allele of the chromosomal locus corresponding to the cloned actin gene of the yeast Saccharomyces cerevisiae has been constructed by DNA transformation with a hybrid plasmid which integrates into, and thereby disrupts, the protein-encoding sequences of the gene. In a diploid strain of yeast, disruption of the actin gene on one chromosome results in a mutation that segregates as a recessive lethal tightly linked to a selectable genetic marker on the integrated plasmid. The actin gene, therefore, must encode an essential function for yeast cell growth.


Assuntos
Actinas/genética , Saccharomyces cerevisiae/genética , Actinas/fisiologia , Alelos , Clonagem Molecular , DNA Fúngico/genética , DNA Recombinante , Genes Letais , Genes Recessivos , Plasmídeos , Recombinação Genética , Transformação Genética
17.
Science ; 243(4888): 231-3, 1989 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-2643162

RESUMO

The protein encoded by SAC6, a gene that can mutate to suppress a temperature-sensitive defect in the yeast actin gene, has been identified as a 67-kilodalton actin-binding protein (ABP 67) that associates with all identifiable actin structures. This finding demonstrates the in vivo functional importance of the actin-ABP 67 interaction previously established in vitro and illustrates the use of suppressor analysis to identify physically interacting proteins.


Assuntos
Actinas/genética , Genes Fúngicos , Genes , Proteínas dos Microfilamentos/genética , Mutação , Saccharomyces cerevisiae/genética , Supressão Genética , Actinas/metabolismo , Proteínas dos Microfilamentos/metabolismo , Mapeamento por Restrição
18.
Science ; 235(4786): 312-7, 1987 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-3541205

RESUMO

In the process of protein secretion, amino-terminal signal sequences are key recognition elements; however, the relation between the primary sequence of an amino-terminal peptide and its ability to function as an export signal remains obscure. The limits of variation permitted for functional signal sequences were determined by replacement of the normal signal sequence of Saccharomyces cerevisiae invertase with essentially random peptide sequences. Since about one-fifth of these sequences can function as an export signal the specificity with which signal sequences are recognized must be very low.


Assuntos
Glicosídeo Hidrolases/metabolismo , Sinais Direcionadores de Proteínas/fisiologia , Sequência de Aminoácidos , Citoplasma/enzimologia , Espaço Extracelular/enzimologia , Glicosilação , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/metabolismo , Relação Estrutura-Atividade , beta-Frutofuranosidase
19.
Science ; 274(5295): 2069-74, 1996 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-8953036

RESUMO

Genetic footprinting was used to assess the phenotypic effects of Ty1 transposon insertions in 268 predicted genes of chromosome V of Saccharomyces cerevisiae. When seven selection protocols were used, Ty1 insertions in more than half the genes tested (157 of 268) were found to result in a detectable reduction in fitness. Results could not be obtained for fewer than 3 percent of the genes tested (7 of 268). Previously known mutant phenotypes were confirmed, and, for about 30 percent of the genes, new mutant phenotypes were identified.


Assuntos
Cromossomos Fúngicos/genética , Genes Fúngicos , Saccharomyces cerevisiae/genética , Clonagem Molecular , Meios de Cultura , Pegada de DNA , Elementos de DNA Transponíveis , DNA Fúngico/genética , Biblioteca Gênica , Mutagênese Insercional , Fenótipo , Reação em Cadeia da Polimerase , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/fisiologia
20.
Science ; 282(5389): 699-705, 1998 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-9784122

RESUMO

Diploid cells of budding yeast produce haploid cells through the developmental program of sporulation, which consists of meiosis and spore morphogenesis. DNA microarrays containing nearly every yeast gene were used to assay changes in gene expression during sporulation. At least seven distinct temporal patterns of induction were observed. The transcription factor Ndt80 appeared to be important for induction of a large group of genes at the end of meiotic prophase. Consensus sequences known or proposed to be responsible for temporal regulation could be identified solely from analysis of sequences of coordinately expressed genes. The temporal expression pattern provided clues to potential functions of hundreds of previously uncharacterized genes, some of which have vertebrate homologs that may function during gametogenesis.


Assuntos
Proteínas de Ligação a DNA , Regulação Fúngica da Expressão Gênica , Meiose/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Esporos Fúngicos/genética , Transcrição Gênica , Animais , Cromossomos Fúngicos/fisiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genes Fúngicos , Genoma Fúngico , Humanos , Morfogênese , Organelas/ultraestrutura , Saccharomyces cerevisiae/fisiologia , Esporos Fúngicos/fisiologia , Esporos Fúngicos/ultraestrutura , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
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