scholarly journals Molecular characterization of CDC42, a Saccharomyces cerevisiae gene involved in the development of cell polarity.

1990 ◽  
Vol 111 (1) ◽  
pp. 143-152 ◽  
Author(s):  
D I Johnson ◽  
J R Pringle

The Saccharomyces cerevisiae CDC42 gene product is involved in the morphogenetic events of the cell division cycle; temperature-sensitive cdc42 mutants are unable to form buds and display delocalized cell-surface deposition at the restrictive temperature (Adams, A. E. M., D. I. Johnson, R. M. Longnecker, B. F. Sloat, and J. R. Pringle. 1990. J. Cell Biol. 111:131-142). To begin a molecular analysis of CDC42 function, we have isolated the CDC42 gene from a yeast genomic DNA library. The use of the cloned DNA to create a deletion of CDC42 confirmed that the gene is essential. Overexpression of CDC42 under control of the GAL10 promoter was not grossly deleterious to cell growth but did perturb the normal pattern of selection of budding sites. Determination of the DNA and predicted amino acid sequences of CDC42 revealed a high degree of similarity in amino acid sequence to the ras and rho (Madaule, P., R. Axel, and A. M. Myers. 1987. Proc. Natl. Acad. Sci. 84:779-783) families of gene products. The similarities to ras proteins (approximately 40% identical or related amino acids overall) were most pronounced in the regions that have been implicated in GTP binding and hydrolysis and in the COOH-terminal modifications leading to membrane association, suggesting that CDC42 function also involves these biochemical properties. The similarities to the rho proteins (approximately 60% identical or related amino acids overall) were more widely distributed through the coding region, suggesting more extensive similarities in as yet undefined biochemical properties and functions.

1992 ◽  
Vol 12 (5) ◽  
pp. 2154-2164 ◽  
Author(s):  
D J DeMarini ◽  
M Winey ◽  
D Ursic ◽  
F Webb ◽  
M R Culbertson

The SEN1 gene, which is essential for growth in the yeast Saccharomyces cerevisiae, is required for endonucleolytic cleavage of introns from all 10 families of precursor tRNAs. A mutation in SEN1 conferring temperature-sensitive lethality also causes in vivo accumulation of pre-tRNAs and a deficiency of in vitro endonuclease activity. Biochemical evidence suggests that the gene product may be one of several components of a nuclear-localized splicing complex. We have cloned the SEN1 gene and characterized the SEN1 mRNA, the SEN1 gene product, the temperature-sensitive sen1-1 mutation, and three SEN1 null alleles. The SEN1 gene corresponds to a 6,336-bp open reading frame coding for a 2,112-amino-acid protein (molecular mass, 239 kDa). Using antisera directed against the C-terminal end of SEN1, we detect a protein corresponding to the predicted molecular weight of SEN1. The SEN1 protein contains a leucine zipper motif, consensus elements for nucleoside triphosphate binding, and a potential nuclear localization signal sequence. The carboxy-terminal 1,214 amino acids of the SEN1 protein are essential for growth, whereas the amino-terminal 898 amino acids are dispensable. A sequence of approximately 500 amino acids located in the essential region of SEN1 has significant similarity to the yeast UPF1 gene product, which is involved in mRNA turnover, and the mouse Mov-10 gene product, whose function is unknown. The mutation that creates the temperature-sensitive sen1-1 allele is located within this 500-amino-acid region, and it causes a substitution for an amino acid that is conserved in all three proteins.


1986 ◽  
Vol 6 (5) ◽  
pp. 1711-1721
Author(s):  
E M McIntosh ◽  
R H Haynes

The dCMP deaminase gene (DCD1) of Saccharomyces cerevisiae has been isolated by screening a Sau3A clone bank for complementation of the dUMP auxotrophy exhibited by dcd1 dmp1 haploids. Plasmid pDC3, containing a 7-kilobase (kb) Sau3A insert, restores dCMP deaminase activity to dcd1 mutants and leads to an average 17.5-fold overproduction of the enzyme in wild-type cells. The complementing activity of the plasmid was localized to a 4.2-kb PvuII restriction fragment within the Sau3A insert. Subcloning experiments demonstrated that a single HindIII restriction site within this fragment lies within the DCD1 gene. Subsequent DNA sequence analysis revealed a 936-nucleotide open reading frame encompassing this HindIII site. Disruption of the open reading frame by integrative transformation led to a loss of enzyme activity and confirmed that this region constitutes the dCMP deaminase gene. Northern analysis indicated that the DCD1 mRNA is a 1.15-kb poly(A)+ transcript. The 5' end of the transcript was mapped by primer extension and appears to exhibit heterogeneous termini. Comparison of the amino acid sequence of the T2 bacteriophage dCMP deaminase with that deduced for the yeast enzyme revealed a limited degree of homology which extends over the entire length of the phage polypeptide (188 amino acids) but is confined to the carboxy-terminal half of the yeast protein (312 amino acids). A potential dTTP-binding site in the yeast and phage enzymes was identified by comparison of homologous regions with the amino acid sequences of a variety of other dTTP-binding enzymes. Despite the role of dCMP deaminase in dTTP biosynthesis, Northern analysis revealed that the DCD1 gene is not subject to the same cell cycle-dependent pattern of transcription recently found for the yeast thymidylate synthetase gene (TMP1).


1986 ◽  
Vol 235 (3) ◽  
pp. 895-898 ◽  
Author(s):  
M S López de Haro ◽  
A Nieto

An almost full-length cDNA coding for pre-uteroglobin from hare lung was cloned and sequenced. The derived amino acid sequence indicated that hare pre-uteroglobin contained 91 amino acids, including a signal peptide of 21 residues. Comparison of the nucleotide sequence of hare pre-uteroglobin cDNA with that previously reported for the rabbit gene indicated five silent point substitutions and six others leading to amino acid changes in the coding region. The untranslated regions of both pre-uteroglobin mRNAs were very similar. The amino acid changes observed are discussed in relation to the different progesterone-binding abilities of both homologous proteins.


1993 ◽  
Vol 11 (2) ◽  
pp. 141-149 ◽  
Author(s):  
S M Duthie ◽  
P L Taylor ◽  
K A Eidne

ABSTRACT The cloning and characterization of the mouse TRH receptor (TRH-R) gene revealed an untranslated exon (exon 1), a single intron and an upstream dinucleotide repeat sequence (d(TG)16.d(AG)21) in the 5′ untranslated region (UTR). The coding region was contained almost entirely on a second exon (exon 2), with the final amino acid and stop codon at the COOH terminus of the gene encoded by a third exon (exon 3) flanked by two introns. The 3′ UTR was contained on the remainder of exon 3 and on the final exon (exon 4). Exon 3 (228 bp) corresponds exactly to a 228 bp deletion that exists in the rat TRH-R cDNA, but not in the mouse cDNA. The mouse TRH-R cDNA encodes a protein of 393 amino acids which is 96% homologous to the rat TRH-R protein of 412 amino acids, but is 19 amino acids shorter at its COOH terminus. The coding sequence for these 19 amino acids (plus 1 extra amino acid) does exist in the mouse TRH-R gene, but the sequence is encoded by exon 4, separated from the rest of the coding region by the stop codon and 223 bp of 3′ UTR on exon 3. Splicing of exon 3 in the mouse TRH-R gene would remove the last amino acid, the stop codon and the 223 bp of 3′ UTR, allowing transcription to continue into the 3′ UTR on exon 4, which encodes the 19 extra amino acids found in the rat cDNA. This would then result in an alternative 412 amino acid version of the mouse TRH-R protein, with 95% homology to the rat TRH-R. This study focused on the structural differences in the intracellular COOH-terminal tail of the receptor, which is known to be a functionally important domain in other members of the G protein-coupled receptor family. We have also recently characterized the human TRH-R cDNA, which revealed a third variant at the COOH terminus. Comparisons between mouse, rat and human TRH-Rs show that the amino acid sequences are virtually identical. However, significant differences between these species exist at the COOH terminus, with each TRH-R having a unique form of the COOH-terminal tail, beginning at exactly the same site and encoding 1, 20 and 6 amino acids in the mouse, rat and human respectively.


1986 ◽  
Vol 6 (5) ◽  
pp. 1711-1721 ◽  
Author(s):  
E M McIntosh ◽  
R H Haynes

The dCMP deaminase gene (DCD1) of Saccharomyces cerevisiae has been isolated by screening a Sau3A clone bank for complementation of the dUMP auxotrophy exhibited by dcd1 dmp1 haploids. Plasmid pDC3, containing a 7-kilobase (kb) Sau3A insert, restores dCMP deaminase activity to dcd1 mutants and leads to an average 17.5-fold overproduction of the enzyme in wild-type cells. The complementing activity of the plasmid was localized to a 4.2-kb PvuII restriction fragment within the Sau3A insert. Subcloning experiments demonstrated that a single HindIII restriction site within this fragment lies within the DCD1 gene. Subsequent DNA sequence analysis revealed a 936-nucleotide open reading frame encompassing this HindIII site. Disruption of the open reading frame by integrative transformation led to a loss of enzyme activity and confirmed that this region constitutes the dCMP deaminase gene. Northern analysis indicated that the DCD1 mRNA is a 1.15-kb poly(A)+ transcript. The 5' end of the transcript was mapped by primer extension and appears to exhibit heterogeneous termini. Comparison of the amino acid sequence of the T2 bacteriophage dCMP deaminase with that deduced for the yeast enzyme revealed a limited degree of homology which extends over the entire length of the phage polypeptide (188 amino acids) but is confined to the carboxy-terminal half of the yeast protein (312 amino acids). A potential dTTP-binding site in the yeast and phage enzymes was identified by comparison of homologous regions with the amino acid sequences of a variety of other dTTP-binding enzymes. Despite the role of dCMP deaminase in dTTP biosynthesis, Northern analysis revealed that the DCD1 gene is not subject to the same cell cycle-dependent pattern of transcription recently found for the yeast thymidylate synthetase gene (TMP1).


1992 ◽  
Vol 12 (5) ◽  
pp. 2154-2164
Author(s):  
D J DeMarini ◽  
M Winey ◽  
D Ursic ◽  
F Webb ◽  
M R Culbertson

The SEN1 gene, which is essential for growth in the yeast Saccharomyces cerevisiae, is required for endonucleolytic cleavage of introns from all 10 families of precursor tRNAs. A mutation in SEN1 conferring temperature-sensitive lethality also causes in vivo accumulation of pre-tRNAs and a deficiency of in vitro endonuclease activity. Biochemical evidence suggests that the gene product may be one of several components of a nuclear-localized splicing complex. We have cloned the SEN1 gene and characterized the SEN1 mRNA, the SEN1 gene product, the temperature-sensitive sen1-1 mutation, and three SEN1 null alleles. The SEN1 gene corresponds to a 6,336-bp open reading frame coding for a 2,112-amino-acid protein (molecular mass, 239 kDa). Using antisera directed against the C-terminal end of SEN1, we detect a protein corresponding to the predicted molecular weight of SEN1. The SEN1 protein contains a leucine zipper motif, consensus elements for nucleoside triphosphate binding, and a potential nuclear localization signal sequence. The carboxy-terminal 1,214 amino acids of the SEN1 protein are essential for growth, whereas the amino-terminal 898 amino acids are dispensable. A sequence of approximately 500 amino acids located in the essential region of SEN1 has significant similarity to the yeast UPF1 gene product, which is involved in mRNA turnover, and the mouse Mov-10 gene product, whose function is unknown. The mutation that creates the temperature-sensitive sen1-1 allele is located within this 500-amino-acid region, and it causes a substitution for an amino acid that is conserved in all three proteins.


1992 ◽  
Vol 12 (7) ◽  
pp. 2924-2930 ◽  
Author(s):  
D J Smith ◽  
A Proudfoot ◽  
L Friedli ◽  
L S Klig ◽  
G Paravicini ◽  
...  

We have previously described a temperature-sensitive pmi40-1 mutant of Saccharomyces cerevisiae which is defective in glycosylation and secretion because of a thermolabile phosphomannose isomerase (PMI) activity. Inactivation of PMI at the restrictive temperature of 37 degrees C prevents synthesis of the GDP-mannose and dolichol-phosphate-mannose required for a number of critical mannosyl transfer reactions and results in cell death. Here, we report the isolation of the PMI40 gene by complementation of the corresponding mutation. The PMI40 gene contains an efficiently spliced intron which differs from the majority of those so far identified in S. cerevisiae in that it is short and the branch-forming structure has an AACTAAC motif replacing the highly conserved consensus TACTAAC. The 48.2-kDa protein predicted to be encoded by PMI40 contains amino acid sequences corresponding to those of internal peptides derived from purified S. cerevisiae PMI. Deletion of the PMI40 coding sequence results in a strain requiring D-mannose for growth. The PMI40 gene is located on chromosome V, and its transcription is increased 12-fold when cells are grown on D-mannose as sole carbon source instead of D-glucose. PMI enzyme activity, however, is not increased in D-mannose-grown cells, and PMI protein levels remain constant, suggesting that the PMI40 gene is subject to additional levels of regulation.


1989 ◽  
Vol 9 (7) ◽  
pp. 3009-3017 ◽  
Author(s):  
Y Nogi ◽  
T Fukasawa

To study the functional domains of a transcriptional repressor encoded by the GAL80 gene of Saccharomyces cerevisiae, we constructed various deletion and insertion mutations in the GAL80 coding region and determined the ability of these mutations to repress synthesis of galactose-metabolizing enzymes as well as the capacity of the mutant proteins to respond to the inducer. Two regions, from amino acids 1 to 321 and from amino acids 341 to 423, in the total sequence of 435 amino acids were required for repression. The internal region from amino acids 321 to 340 played a role in the response to the inducer. The 12 amino acids at the carboxy terminus were dispensable for normal functioning of the GAL80 protein. Using indirect immunofluorescence and subcellular fractionation techniques, we also found that two distinct regions (amino acids 1 to 109 and 342 to 405) within the putative repression domain were capable of directing cytoplasmically synthesized Escherichia coli beta-galactosidase to the yeast nucleus. In addition, three gal80 mutations were mapped at amino acid residues 183, 298, and 310 in the domain required for repression. On the basis of these results, we suggest that the GAL80 protein consists of a repression domain located in two separate regions (amino acid residues 1 to 321 and 341 to 423) that are interrupted by an inducer interaction domain (residues 322 to 340) and two nuclear localization domains (1 to 109 and 342 to 405) that overlap the repression domains.


2001 ◽  
Vol 183 (21) ◽  
pp. 6265-6273 ◽  
Author(s):  
Kenji Tsuge ◽  
Takanori Akiyama ◽  
Makoto Shoda

ABSTRACT Bacillus subtilis RB14 is a producer of the antifungal lipopeptide iturin A. Using a transposon, we identified and cloned the iturin A synthetase operon of RB14, and the sequence of this operon was also determined. The iturin A operon spans a region that is more than 38 kb long and is composed of four open reading frames, ituD, ituA, ituB, and ituC. The ituD gene encodes a putative malonyl coenzyme A transacylase, whose disruption results in a specific deficiency in iturin A production. The second gene, ituA, encodes a 449-kDa protein that has three functional modules homologous to fatty acid synthetase, amino acid transferase, and peptide synthetase. The third gene, ituB, and the fourth gene, ituC, encode 609- and 297-kDa peptide synthetases that harbor four and two amino acid modules, respectively. Mycosubtilin, which is produced by B. subtilis ATCC 6633, has almost the same structure as iturin A, but the amino acids at positions 6 and 7 in the mycosubtilin sequence ared-Ser→l-Asn, while in iturin A these amino acids are inverted (i.e., d-Asn→l-Ser). Comparison of the amino acid sequences encoded by the iturin A operon and the mycosubtilin operon revealed that ituD, ituA, andituB have high levels of homology to the counterpart genesfenF (79%), mycA (79%), and mycB(79%), respectively. Although the overall level of homology of the amino acid sequences encoded by ituC andmycC, the counterpart of ituC, is relatively low (64%), which indicates that there is a difference in the amino acid sequences of the two lipopeptides, the levels of homology between the putative serine adenylation domains and between the asparagine adenylation domains in the two synthetases are high (79 and 80%, respectively), implying that there is an intragenic domain change in the synthetases. The fact that the flanking sequence of the iturin A synthetase coding region was highly homologous to the flanking sequence that of xynD of B. subtilis 168 and the fact that the promoter of the iturin A operon which we identified was also conserved in an upstream sequence of xynD imply that horizontal transfer of this operon occurred. When the promoter was replaced by the repU promoter of the plasmid pUB110 replication protein, production of iturin A increased threefold.


2016 ◽  
Vol 14 (1) ◽  
pp. 105-113
Author(s):  
Hoàng Thị Thao ◽  
Hồ Mạnh Tường ◽  
Nguyễn Thị Ngọc Lan ◽  
Nguyễn Vũ Thanh Thanh ◽  
Nguyễn Văn Sơn ◽  
...  

Plant defensins play a role against the seed-feeding insects. Defensin associates with the center of α-amylase activity in the gut of weevils, thus inhibiting the digestion of starch by weevils. In this study, the resistance of eight mungbean cultivars to weevils was evaluated by the method of artificial weevils infection. The Tam TH cultivar had lowest index of susceptibility to weevils (634.63) and DX22 cultivar had highest index (1058.72), and the highest resistance to weevils was found in Tam TH and DX22 was found to have the lowest resistance. VrPDF1 genes isolated from mungbean cultivars are 356 bp in length with two exons interrupted by an intron. The coding region of the VrPDF1 gene is 228 bp in length, encoding 75 amino acids. The comparative results of the nucleotide sequence of cDNA between Tam TH  and DX22 showed that there was a difference in 13 nucleotides and comparison of amino acid sequences of the deduced protein indicated that there was a difference in 9 amino acids. Within the intron region of the VrPDF1 genes there was difference in 5 nucleotides. The genetic distance based on nucleotide sequences of the coding region of VrPDF1 gene of DX22 and seven other mungbean cultivars is 6.2% and based on the amino acid sequence deduced is 7.7%. The coding region of the VrPDF1 gene of DX22 was used to create a transformation vector aimed at creating weevil-resistant transgenic mungbean.


Sign in / Sign up

Export Citation Format

Share Document