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K F Beck

Publications and source records attributed to K F Beck.

25 records · Page 2Linked to original sources
PubMed1994

The tripartite DNA element responsible for diet-induced rat fatty acid synthase (FAS) regulation.

We investigated which region of the 5'-flanking sequence of the rat fatty acid synthase (FAS)-encoding gene could be responsible for its nutritionally regulated expression. Diet-induced differences in chromatin structure were determined by DNase I treatment of intact nuclei from hepatic tissue. A low-fat diet results in a different pattern of DNase I-hypersensitive sites (HS) in the chromatin of the FAS promoter (pFAS) from that seen when the nuclear extract was prepared from the livers of normally fed rats. The protein-binding properties of the region defined by DNase I hypersensitivity were tested by gel retardation. A putative cis-acting element with a tripartite structure, 5'-GCCT, 6-bp spacer and a 3'-palindrome, could be localized between bp -518 to -495 in pFAS. Competition experiments with oligodeoxyribonucleotides (oligos) representing subfragments of this cis-element showed that the requirement for structure is stricter than that for sequence. This element could be one of the termini of the insulin-induced signal cascade.

Animals↗
PubMed1994

Phosphoribosylpyrophosphate synthetase (PRS): a new gene family in Saccharomyces cerevisiae.

Saccharomyces cerevisiae contains at least four PRS genes, all of which have been cloned and sequenced. Each of the four derived amino acid sequences have more than 60% similarity to the corresponding polypeptides of man, rat, Escherichia coli and Salmonella typhimurium. The PRS1 gene maps on chromosome XI, PRS2 on chromosome V, PRS3 on chromosome VIII and PRS4 on chromosome II. One member of this gene family, PRS1, contains a region of non-homology (NHR) shown by cDNA cloning and sequencing not to be an intron. The results presented here suggest that the presence of this NHR is not detrimental to the function of the gene. To date the possibility of protein splicing can be neither proven nor disputed.

Amino Acid Sequence↗
PubMed1992

The fatty acid synthase (FAS) gene and its promoter in Rattus norvegicus.

Screening of rat liver genomic libraries yielded 5 overlapping clones for rat fatty acid synthase (FAS). From these clones we determined the 18,170 bp sequence of the rat FAS together with 5,028 bp of the 5'-flanking region and 515 bp of the 3'-adjacent genomic sequence. The two FAS transcripts which differ only in the positions of their polyadenylation/termination sites consist of one untranslated and 42 translated exons. Surprisingly, the substrate binding site for enoyl reductase, one of the FAS component functions, is interrupted by an intron. The sizes and the boundaries of the individual domains could be mapped in relation to the exon/intron structure of the gene. These eight partial functions coincide with discrete units of exons. The acyl carrier protein with its prosthetic 4'-phosphopantetheine group is located within a single exon supporting the idea that rat FAS has evolved by gene fusion. Using primer extension the main transcription start site of the FAS mRNA in both hepatic and mammary gland tissues was located at 5,028 bp in the sequence determined. As expected of a gene which is pretranslationally regulated the 5'-flanking region contains, in addition to TATA and CAAT boxes, consensus sequences for several DNA binding proteins.

Amino Acid Sequence↗
PubMed1991

The pentafunctional FAS1 genes of Saccharomyces cerevisiae and Yarrowia lipolytica are co-linear and considerably longer than previously estimated.

The fatty acid synthetase (FAS) gene FAS1 of the alkane-utilizing yeast Yarrowia lipolytica was cloned and sequenced. The gene is represented by an intron-free reading frame of 6228 bp encoding a protein of 2076 amino acids and 229,980 Da molecular weight. This protein exhibits a 58% sequence similarity to the corresponding Saccharomyces cerevisiae FAS beta-subunit. The sequential order of the five FAS1-encoded enzyme The sequential order of the five FAS1-encoded enzyme domains, acetyl transferase, enoyl reductase, dehydratase and malonyl/palmityl-transferase, is co-linear in both organisms. This finding agrees with available evidence that the functional organization of FAS genes is similar in related organisms but differs considerably between unrelated species. In addition, previously reported conflicting data concerning the 3' end of S. cerevisiae FAS1 were re-examined by genomic and cDNA sequencing of the relevant portion of the gene. Thereby, the translational stop codon was shown to lie considerably downstream of both published termination sites. The S. cerevisiae FAS1 gene thus has a corrected length of 6153 bp and encodes a protein of 2051 amino acids and 228,667 Da molecular weight.

Amino Acid Sequence↗
PubMed1989

Rat mammary gland fatty acid synthase: localization of the constituent domains and two functional polyadenylation/termination signals in the cDNA.

The rat fatty acid synthase (FAS) is active only as a dimer, although the eight component functions are contained in a single polypeptide chain. Using mRNA from lactating rat mammary glands a cDNA expression library was established. With the overlapping immunologically positive clones we have an 8.9kb cDNA sequence for rat FAS. In the 3'-nontranslated region of the rat FAS cDNA we find a prototype polyadenylation/termination signal and 779 nucleotides upstream, a mutated one. Both of these polyadenylation/termination signals are used and give rise to two equally abundant mRNA species which are coordinately regulated. In the derived amino acid sequence we could locate six of the eight component functions; their order is NH2- beta-ketoacyl synthase - acetyl/malonyl transferases -enoyl reductase - acyl carrier protein - thioesterase -COOH. Comparison of FAS from different sources shows that the primary sequence is conserved only for the active residues and the amino acids in their immediate vicinity.

Amino Acid Sequence↗
PubMed1988

Isolation and sequence analysis of the fatty acid synthetase FAS2 gene from Penicillium patulum.

The fatty acid synthetase complex of Penicillium patulum was isolated and shown to be structurally similar to other known fungal fatty acid synthetases. It is composed of two subunit, alpha and beta, each with a molecular mass of about 200 kDa. P. patulum genomic and cDNA libraries were constructed in lambda gt11 and EMBL3 vectors. From these libraries, the P. patulum FAS2 gene together with its flanking DNA was isolated. The cloned genomic DNA was sequenced over a length of 6357 base pairs. The coding sequence of fatty acid synthetase subunit alpha, being 5571 nucleotides long, was identified within this DNA segment. The FAS2 gene is a mosaic of three exons (514, 4949 and 108 base pairs) and two introns, each of 54 base pairs in length. Both introns were absent in the corresponding cDNA sequences. Like other fungal introns both contain an internal CTAAC sequence, located 10 base pairs upstream of their 3'-exon/intron boundaries. In addition, they have, at their ends, the GTCAAGT and TAG consensus sequences characteristic of all eucaryotic introns. Furthermore, two pairs of direct repeats, of as yet unknown significance, were found in the two P. patulum introns. The P. patulum FAS2 gene encodes a protein of 1857 amino acids and 204.5 kDa molecular mass. It is 90 nucleotides shorter than the corresponding S. cerevisiae gene. In both organisms, the FAS2 genes and their products exhibit a high degree of overall sequence similarity at both the DNA (63%) and protein (68%) levels. Therefore, the fatty acid synthetase alpha subunits of P. patulum and S. cerevisiae obviously contain the same catalytic domains in an identical sequential order.

Amino Acid Sequence↗