5'-Noncoding sequences have been compiled from 699 vertebrate mRNAs. (GCC) GCCA/GCCATGG emerges as the consensus sequence for initiation of translation in vertebrates. The most highly conserved position in that motif is the purine in position -3 (three nucleotides upstream from the ATG codon); 97% of vertebrate mRNAs have a purine, most often A, in that position. The periodical occurrence of G (in positions -3, -6, -9) is discussed. Upstream ATG codons occur in fewer than 10% of vertebrate mRNAs-at-large; a notable exception are oncogene transcripts, two-thirds of which have ATG codons preceding the start of the major open reading frame. The leader sequences of most vertebrate mRNAs fall in the size range of 20 to 100 nucleotides. The significance of shorter and longer 5'-noncoding sequences is discussed.

An analysis of 5'-noncoding sequences from 699 vertebrate messenger RNAs

It is likely that most vertebrate genes are associated with 'HTF islands'--DNA sequences in which CpG is abundant and non-methylated. Highly tissue-specific genes, though, usually lack islands. The contrast between islands and the remainder of the genome may identify sequences that are to be constantly available in the nucleus. DNA methylation appears to be involved in this function, rather than with activation of tissue specific genes.

CpG-rich islands and the function of DNA methylation

CpG islands in vertebrate genomes.

systemic reaction characterized by fever, leukocytosis, increase in erythrocyte sedimentation rate, increases in Leucocytosis secretion of ACTH and glucocorticoids, activation of Complement activat complement and clotting cascades, decreases in serum levels of iron and zinc, a negative nitrogen balance, and by dramatic changes in the concentration of some plasma ,l' proteins. These proteins are named acute phase proteins. i

Interleukin-6 and the acute phase response

The ferritins: molecular properties, iron storage function and cellular regulation☆

Cell-specific expression of a transfected human α1-antitrypsin gene

https://www.cell.com/cell/pdf/0092-8674(83)90058-2.pdf

Common and interchangeable elements in the promoters of genes transcribed by RNA polymerase III

Human genomic clones of the haptoglobin Hp1F and the "haptoglobin related' gene (Hpr) have been isolated. The two genes are adjacent, spanning a region of approximately 21 kb. A comparison of their coding sequences shows that Hpr differs from Hp1F at 28 codons. Northern blot and primer elongation analyses with human liver RNA show that the haptoglobin gene Hp1F appears to be transcribed some 1000-fold less in fetal than in adult liver. In adult liver the amount of Hpr mRNA is at the lower limit of detection, therefore the extent of its expression is at most less than 1000-fold that of the Hp1F gene. No Hpr mRNA can be detected in fetal liver.

Structure and expression of the human haptoglobin locus.

Ferritin is composed of two subunits, H and L. cDNA's coding for these proteins from human liver (1,2,3), lymphocytes (4) and from the monocyte-like cell line U937 (5) have been cloned and sequenced. Southern blot analysis on total human DNA reveals that there are many DNA segments hybridizing to the apoferritin H and L cDNA probes (1,2,4,6). In view of the tissue heterogeneity of ferritin molecules (7,8), it appeared possible that apoferritin molecules could be coded by a family of genes differentially expressed in various tissues (1,2). In this paper we describe the cloning and sequencing of the gene coding for human apoferritin H. This gene has three introns; the exon sequence is identical to that of cDNA's isolated from human liver, lymphocytes, HeLa cells and endothelial cells. In addition we show that at least 15 intronless pseudogenes exist, with features suggesting that they were originated by reverse transcription and insertion. On the basis of these results we conclude that only one gene is responsible for the synthesis of the majority of apoferritin H mRNA in various tissues examined, and that probably all the other DNA segments hybridizing with apoferritin cDNA are pseudogenes.

Structure of gene and pseudogenes of human apoferritin H

The human genome contains three alpha 1-glycoprotein genes (AGP-A, AGP-B, and AGP-B') encoding for slightly different forms of the protein. The major component of human alpha 1-acid glycoprotein found in plasma is coded by AGP-A, which is expressed in liver and in hepatoma cell lines and is induced by inflammatory stimuli. We have studied the regulation of the cloned AGP-A gene by transfection into cell lines of hepatic and nonhepatic origin. Unlike any other liver-specific gene investigated so far, every AGP construct tested was expressed with comparable efficiency in hepatoma and HeLa cells. In contrast, identical constructs in transgenic mice are expressed in a tissue-specific manner and are regulated by acute-phase stimuli. Transgenic mice carrying the cluster of three AGP genes secrete the human protein in the serum, and the corresponding mRNA is mainly derived from the AGP-A gene. The mRNA is liver specific, and its concentration increases several fold following experimentally induced inflammation. Additional transgenic lines carrying only the AGP-A gene showed that sufficient information for tissue-specific and regulated expression is contained within a 6.6-kb segment comprising the whole coding region plus 1.2-kb 5'-flanking and 2-kb 3'-flanking DNA.

/pdf/expression-of-human-alpha-1-acid-glycoprotein-genes-in-51isabmkke.pdf

Riccardo Cortese

Papers

Cell-specific expression of a transfected human α1-antitrypsin gene

Common and interchangeable elements in the promoters of genes transcribed by RNA polymerase III

Structure and expression of the human haptoglobin locus.

Structure of gene and pseudogenes of human apoferritin H

Expression of human alpha 1-acid glycoprotein genes in cultured cells and in transgenic mice.