Ribosomal protein S14 is encoded by a pair of highly conserved, adjacent genes on the X chromosome of Drosophila melanogaster

We describe a Drosophila DNA clone of tandemly duplicated genes encoding an amino acid sequence nearly identical to human ribosomal protein S14 and yeast rp59. Despite their remarkably similar exons, the locations and sizes of introns differ radically among the Drosophila, human, and yeast (Saccharomyces cerevisiae) ribosomal protein genes. Transcripts of both Drosophila RPS14 genes were detected in embryonic and adult tissues and are the same length as mammalian S14 message. Drosophila RPS14 was mapped to region 7C5-9 on the X chromosome. This interval also encodes a previously characterized Minute locus, M(1)7C.

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Yeast NOP2 encodes an essential nucleolar protein with homology to a human proliferation marker.

The Journal of Cell Biology ◽

10.1083/jcb.127.6.1799 ◽

1994 ◽

Vol 127 (6) ◽

pp. 1799-1813 ◽

Cited By ~ 49

Author(s):

E de Beus ◽

J S Brockenbrough ◽

B Hong ◽

J P Aris

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Ribosomal Protein ◽

Nucleolar Protein ◽

Mrna Levels ◽

Multicopy Plasmid ◽

Yeast Saccharomyces Cerevisiae ◽

Protein Levels ◽

Significant Amino Acid Sequence ◽

Ribosomal Protein L3

We have isolated a gene (NOP2) encoding a nucleolar protein during a search for previously unidentified nuclear proteins in the yeast Saccharomyces cerevisiae. The protein encoded by NOP2 (Nop2p) has a predicted molecular mass of 70 kD, migrates at 90 kD by SDS-PAGE, and is essential for cell viability. Nop2p shows significant amino acid sequence homology to a human proliferation-associated nucleolar protein, p120. Approximately half of Nop2p exhibits 67% amino acid sequence identity to p120. Analysis of subcellular fractions indicates that Nop2p is located primarily in the nucleus, and nuclear fractionation studies suggest that Nop2p is associated with the nucleolus. Indirect immunofluorescence localization of Nop2p shows a nucleolar-staining pattern, which is heterogeneous in appearance, and a faint staining of the cytoplasm. The expression of NOP2 during the transition from stationary phase growth arrest to rapid growth was measured, and compared to the expression of TCM1, which encodes the ribosomal protein L3. Nop2p protein levels are markedly upregulated during the onset of growth, compared to the levels of ribosomal protein L3, which remain relatively constant. NOP2 mRNA levels also increase during the onset of growth, accompanied by a similar increase in the levels of TCM1 mRNA. The consequences of overexpressing NOP2 from the GAL10 promoter on a multicopy plasmid were investigated. Although NOP2 overexpression produced no discernible growth phenotype and had no effect on ribosome subunit synthesis, overexpression was found to influence the morphology of the nucleolus, as judged by electron microscopy. Overexpression caused the nucleolus to become detached from the nuclear envelope and to become more rounded and/or fragmented in appearance. These findings suggest roles for NOP2 in nucleolar function during the onset of growth, and in the maintenance of nucleolar structure.

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Association of RAP1 binding sites with stringent control of ribosomal protein gene transcription in Saccharomyces cerevisiae

Molecular and Cellular Biology ◽

10.1128/mcb.11.5.2723-2735.1991 ◽

1991 ◽

Vol 11 (5) ◽

pp. 2723-2735 ◽

Cited By ~ 1

Author(s):

C M Moehle ◽

A G Hinnebusch

Keyword(s):

Gene Expression ◽

Saccharomyces Cerevisiae ◽

Amino Acid ◽

Ribosomal Protein ◽

Binding Sites ◽

Protein Gene ◽

Ribosomal Protein Gene ◽

Ribosomal Protein Genes ◽

Biosynthetic Genes ◽

Stringent Control

An amino acid limitation in bacteria elicits a global response, called stringent control, that leads to reduced synthesis of rRNA and ribosomal proteins and increased expression of amino acid biosynthetic operons. We have used the antimetabolite 3-amino-1,2,4-triazole to cause histidine limitation as a means to elicit the stringent response in the yeast Saccharomyces cerevisiae. Fusions of the yeast ribosomal protein genes RPL16A, CRY1, RPS16A, and RPL25 with the Escherichia coli lacZ gene were used to show that the expression of these genes is reduced by a factor of 2 to 5 during histidine-limited exponential growth and that this regulation occurs at the level of transcription. Stringent regulation of the four yeast ribosomal protein genes was shown to be associated with a nucleotide sequence, known as the UASrpg (upstream activating sequence for ribosomal protein genes), that binds the transcriptional regulatory protein RAP1. The RAP1 binding sites also appeared to mediate the greater ribosomal protein gene expression observed in cells growing exponentially than in cells in stationary phase. Although expression of the ribosomal protein genes was reduced in response to histidine limitation, the level of RAP1 DNA-binding activity in cell extracts was unaffected. Yeast strains bearing a mutation in any one of the genes GCN1 to GCN4 are defective in derepression of amino acid biosynthetic genes in 10 different pathways under conditions of histidine limitation. These Gcn- mutants showed wild-type regulation of ribosomal protein gene expression, which suggests that separate regulatory pathways exist in S. cerevisiae for the derepression of amino acid biosynthetic genes and the repression of ribosomal protein genes in response to amino acid starvation.

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The Saccharomyces cerevisiae ACP2 gene encodes an essential HMG1-like protein

Molecular and Cellular Biology ◽

10.1128/mcb.8.3.1282-1289.1988 ◽

1988 ◽

Vol 8 (3) ◽

pp. 1282-1289

Author(s):

W Haggren ◽

D Kolodrubetz

Keyword(s):

Saccharomyces Cerevisiae ◽

Amino Acid ◽

Amino Acid Sequence ◽

High Mobility ◽

Hmg Proteins ◽

Gene Encoding ◽

Yeast Saccharomyces Cerevisiae ◽

Dna Library ◽

Associated Proteins ◽

Genomic Dna Library

The high-mobility-group (HMG) proteins, a group of nonhistone chromatin-associated proteins, have been extensively characterized in higher eucaryotic cells. To test the biological function of an HMG protein, we have cloned and mutagenized a gene encoding an HMG-like protein from the yeast Saccharomyces cerevisiae. A yeast genomic DNA library was screened with an oligonucleotide designed to hybridize to any yeast gene containing an amino acid sequence conserved in several higher eucaryotic HMG proteins. DNA sequencing and Northern (RNA) blot analysis revealed that one gene, called ACP2 (acidic protein 2), synthesizes a poly(A)+ RNA in S. cerevisiae which encodes a 27,000-molecular-weight protein whose amino acid sequence is homologous to those of calf HMG1 and HMG2 and trout HMGT proteins. Standard procedures were used to construct a diploid yeast strain in which one copy of the ACP2 gene was mutated by replacement with the URA3 gene. When this diploid was sporulated and dissected, only half of the spores were viable. About half of the nonviable spores proceeded through two or three cell divisions and then stopped dividing; the rest did not germinate at all. None of the viable spores contained the mutant ACP2 gene, thus proving that the protein encoded by ACP2 is required for cell viability. The results presented here demonstrate that an HMG-like protein has an essential physiological function.

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Protease B of the lysosomelike vacuole of the yeast Saccharomyces cerevisiae is homologous to the subtilisin family of serine proteases.

Molecular and Cellular Biology ◽

10.1128/mcb.7.12.4390 ◽

1987 ◽

Vol 7 (12) ◽

pp. 4390-4399 ◽

Cited By ~ 103

Author(s):

C M Moehle ◽

R Tizard ◽

S K Lemmon ◽

J Smart ◽

E W Jones

Keyword(s):

Saccharomyces Cerevisiae ◽

Molecular Weight ◽

Amino Acid ◽

Amino Acid Sequence ◽

Serine Proteases ◽

Proteinase K ◽

Yeast Saccharomyces Cerevisiae ◽

Amino Terminal ◽

Protease B ◽

Mature Protease

The PRB1 gene of Saccharomyces cerevisiae encodes the vacuolar endoprotease protease B. We have determined the DNA sequence of the PRB1 gene and the amino acid sequence of the amino terminus of mature protease B. The deduced amino acid sequence of this serine protease shares extensive homology with those of subtilisin, proteinase K, and related proteases. The open reading frame of PRB1 consists of 635 codons and, therefore, encodes a very large protein (molecular weight, greater than 69,000) relative to the observed size of mature protease B (molecular weight, 33,000). Examination of the gene sequence, the determined amino-terminal sequence, and empirical molecular weight determinations suggests that the preproenzyme must be processed at both amino and carboxy termini and that asparagine-linked glycosylation occurs at an unusual tripeptide acceptor sequence.

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Structure and expression of the Drosophila ubiquitin-52-amino-acid fusion-protein gene

Biochemical Journal ◽

10.1042/bj2860281 ◽

1992 ◽

Vol 286 (1) ◽

pp. 281-288 ◽

Cited By ~ 10

Author(s):

H L Cabrera ◽

R Barrio ◽

C Arribas

Keyword(s):

Drosophila Melanogaster ◽

Amino Acid ◽

Fusion Protein ◽

Ribosomal Protein ◽

Protein Gene ◽

Genomic Library ◽

Regulatory Region ◽

Ribosomal Protein Genes ◽

Common Features ◽

Drosophila Cells

Ubiquitin belongs to a multigene family. In Drosophila two members of this family have been previously described. We report here the organization and expression of a third member, the DUb52 gene, isolated by screening a Drosophila melanogaster genomic library. This gene encodes an ubiquitin monomer fused to a 52-amino acid extension protein. There are no introns interrupting the coding sequence. Recently, it has been described that this extension encodes a ribosomal protein in Saccharomyces, Dictyostelium, and Arabidopsis. The present results show that the 5′ regulatory region of DUb52 shares common features with the ribosomal protein genes of Drosophila, Xenopus and mouse, including GC- and pyrimidine-rich regions. Moreover, sequences similar to the consensus Ribo-box in Neurospora crassa have been identified. Furthermore, a sequence has been found that is similar to the binding site for the TFIIIA distal element factor from Xenopus laevis. The DUb52 gene is transcribed to a 0.9 kb mRNA that is expressed constitutively throughout development and is particularly abundant in ovaries. In addition, the DUb52 gene has been found to be preferentially transcribed in exponentially growing Drosophila cells.

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Association of RAP1 binding sites with stringent control of ribosomal protein gene transcription in Saccharomyces cerevisiae.

Molecular and Cellular Biology ◽

10.1128/mcb.11.5.2723 ◽

1991 ◽

Vol 11 (5) ◽

pp. 2723-2735 ◽

Cited By ~ 104

Author(s):

C M Moehle ◽

A G Hinnebusch

Keyword(s):

Gene Expression ◽

Saccharomyces Cerevisiae ◽

Amino Acid ◽

Ribosomal Protein ◽

Binding Sites ◽

Protein Gene ◽

Ribosomal Protein Gene ◽

Ribosomal Protein Genes ◽

Biosynthetic Genes ◽

Stringent Control

An amino acid limitation in bacteria elicits a global response, called stringent control, that leads to reduced synthesis of rRNA and ribosomal proteins and increased expression of amino acid biosynthetic operons. We have used the antimetabolite 3-amino-1,2,4-triazole to cause histidine limitation as a means to elicit the stringent response in the yeast Saccharomyces cerevisiae. Fusions of the yeast ribosomal protein genes RPL16A, CRY1, RPS16A, and RPL25 with the Escherichia coli lacZ gene were used to show that the expression of these genes is reduced by a factor of 2 to 5 during histidine-limited exponential growth and that this regulation occurs at the level of transcription. Stringent regulation of the four yeast ribosomal protein genes was shown to be associated with a nucleotide sequence, known as the UASrpg (upstream activating sequence for ribosomal protein genes), that binds the transcriptional regulatory protein RAP1. The RAP1 binding sites also appeared to mediate the greater ribosomal protein gene expression observed in cells growing exponentially than in cells in stationary phase. Although expression of the ribosomal protein genes was reduced in response to histidine limitation, the level of RAP1 DNA-binding activity in cell extracts was unaffected. Yeast strains bearing a mutation in any one of the genes GCN1 to GCN4 are defective in derepression of amino acid biosynthetic genes in 10 different pathways under conditions of histidine limitation. These Gcn- mutants showed wild-type regulation of ribosomal protein gene expression, which suggests that separate regulatory pathways exist in S. cerevisiae for the derepression of amino acid biosynthetic genes and the repression of ribosomal protein genes in response to amino acid starvation.

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