Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
J Mol Evol
2004 Nov 01;595:674-86. doi: 10.1007/s00239-004-2659-y.
Show Gene links
Show Anatomy links
Sequence and functional conservation of the intergenic region between the head-to-head genes encoding the small heat shock proteins alphaB-crystallin and HspB2 in the mammalian lineage.
Doerwald L
,
van Rheede T
,
Dirks RP
,
Madsen O
,
Rexwinkel R
,
van Genesen ST
,
Martens GJ
,
de Jong WW
,
Lubsen NH
.
???displayArticle.abstract???
An unexpected feature of the large mammalian genome is the frequent occurrence of closely linked head-to-head gene pairs. Close apposition of such gene pairs has been suggested to be due to sharing of regulatory elements. We show here that the head-to-head gene pair encoding two small heat shock proteins, alphaB-crystallin and HspB2, is closely linked in all major mammalian clades, suggesting that this close linkage is of selective advantage. Yet alphaB-crystallin is abundantly expressed in lens and muscle and in response to a heat shock, while HspB2 is abundant only in muscle and not upregulated by a heat shock. The intergenic distance between the genes for these two proteins in mammals ranges from 645 bp (platypus) to 1069 bp (opossum), with an average of about 900 bp; in chicken the distance was the same as in duck (1.6 kb). Phylogenetic footprinting and sequence alignment identified a number of conserved sequence elements close to the HspB2 promoter and two farther upstream. All known regulatory elements of the mouse alphaB-crystallin promoter are conserved, except in platypus and birds. The lens-specific region 1 (LSR1) and the heat shock elements (HSEs) lack in birds; in platypus the LSR1 is reduced to a Pax-6 site, while the Pax-6 site in LSR2 and a HSE are absent. Most likely the primordial mammalian alphaB-crystallin promoter had two LSRs and two HSEs. In transfection experiments the platypus alphaB-crystallin promoter retained heat shock responsiveness and lens expression. It also directed lens expression in Xenopus laevis transgenes, as did the HspB2 promoter of rat or blind mole rat. Deletion of the middle of the intergenic region including the upstream enhancer affected the activity of both the rat alphaB-crystallin and the HspB2 promoters, suggesting sharing of the enhancer region by the two promoters.
Adachi,
Bidirectional gene organization: a common architectural feature of the human genome.
2002, Pubmed
Adachi,
Bidirectional gene organization: a common architectural feature of the human genome.
2002,
Pubmed
Bell,
The protein CTCF is required for the enhancer blocking activity of vertebrate insulators.
1999,
Pubmed
Brakenhoff,
Transgenic Xenopus laevis tadpoles: a transient in vivo model system for the manipulation of lens function and lens development.
1991,
Pubmed
,
Xenbase
Burgess-Beusse,
The insulation of genes from external enhancers and silencing chromatin.
2002,
Pubmed
Burke,
Molecular cloning and expression of the chromatin insulator protein CTCF in Xenopus laevis.
2002,
Pubmed
,
Xenbase
Chamberlain,
Evidence that fibroblast growth factor promotes lens fibre differentiation.
1987,
Pubmed
Dermitzakis,
Evolution of transcription factor binding sites in Mammalian gene regulatory regions: conservation and turnover.
2002,
Pubmed
Dubin,
Expression of the murine alpha B-crystallin gene in lens and skeletal muscle: identification of a muscle-preferred enhancer.
1991,
Pubmed
Foo,
NF-kappaB to the rescue: RELs, apoptosis and cellular transformation.
1999,
Pubmed
Gopal-Srivastava,
Involvement of retinoic acid/retinoid receptors in the regulation of murine alphaB-crystallin/small heat shock protein gene expression in the lens.
1998,
Pubmed
Gopal-Srivastava,
The murine alpha B-crystallin/small heat shock protein enhancer: identification of alpha BE-1, alpha BE-2, alpha BE-3, and MRF control elements.
1993,
Pubmed
Gopal-Srivastava,
Regulation of the murine alpha B-crystallin/small heat shock protein gene in cardiac muscle.
1995,
Pubmed
Gopal-Srivastava,
Pax-6 and alphaB-crystallin/small heat shock protein gene regulation in the murine lens. Interaction with the lens-specific regions, LSR1 and LSR2.
1996,
Pubmed
Gopal-Srivastava,
Identification of a lens-specific regulatory region (LSR) of the murine alpha B-crystallin gene.
1994,
Pubmed
Hansen,
Genomic structure of the human mitochondrial chaperonin genes: HSP60 and HSP10 are localised head to head on chromosome 2 separated by a bidirectional promoter.
2003,
Pubmed
Hough,
Adaptive evolution of small heat shock protein/alpha B-crystallin promoter activity of the blind subterranean mole rat, Spalax ehrenbergi.
2002,
Pubmed
Ishihara,
An evolutionarily conserved putative insulator element near the 3' boundary of the imprinted Igf2/H19 domain.
2002,
Pubmed
Iwaki,
Identification and characterization of the gene encoding a new member of the alpha-crystallin/small hsp family, closely linked to the alphaB-crystallin gene in a head-to-head manner.
1997,
Pubmed
Jansen,
Transgene-driven protein expression specific to the intermediate pituitary melanotrope cells of Xenopus laevis.
2002,
Pubmed
,
Xenbase
Kadonaga,
The DPE, a core promoter element for transcription by RNA polymerase II.
2002,
Pubmed
Kappé,
The human genome encodes 10 alpha-crystallin-related small heat shock proteins: HspB1-10.
2003,
Pubmed
Klok,
Induction and maintenance of differentiation of rat lens epithelium by FGF-2, insulin and IGF-1.
1998,
Pubmed
Kuhn,
Genomic insulators: connecting properties to mechanism.
2003,
Pubmed
Labrador,
Setting the boundaries of chromatin domains and nuclear organization.
2002,
Pubmed
Meyer,
Human poly(ADP-ribose) glycohydrolase (PARG) gene and the common promoter sequence it shares with inner mitochondrial membrane translocase 23 (TIM23).
2003,
Pubmed
Ohlsson,
CTCF is a uniquely versatile transcription regulator linked to epigenetics and disease.
2001,
Pubmed
Otte,
The Pxmp2 and PoleI genes are linked by a bidirectional promoter in an evolutionary conserved fashion.
2003,
Pubmed
Peek,
DNA methylation as a regulatory mechanism in rat gamma-crystallin gene expression.
1991,
Pubmed
Phillips,
The virtuoso of versatility: POU proteins that flex to fit.
2000,
Pubmed
Posada,
MODELTEST: testing the model of DNA substitution.
1998,
Pubmed
Schuettengruber,
Alternate activation of two divergently transcribed mouse genes from a bidirectional promoter is linked to changes in histone modification.
2003,
Pubmed
Shaw,
Ternary complex factors: prime nuclear targets for mitogen-activated protein kinases.
2003,
Pubmed
Shin,
The CaTin1 (Capsicum annuum TMV-induced clone 1) and CaTin1-2 genes are linked head-to-head and share a bidirectional promoter.
2003,
Pubmed
Shinya,
Identification of two initiator elements in the bidirectional promoter of the human dihydrofolate reductase and mismatch repair protein 1 genes.
1994,
Pubmed
Springer,
Molecules consolidate the placental mammal tree.
2004,
Pubmed
Srinivasan,
Complete structure and expression of the rat alpha B-crystallin gene.
1994,
Pubmed
Suzuki,
MKBP, a novel member of the small heat shock protein family, binds and activates the myotonic dystrophy protein kinase.
1998,
Pubmed
Swamynathan,
Orientation-dependent influence of an intergenic enhancer on the promoter activity of the divergently transcribed mouse Shsp/alpha B-crystallin and Mkbp/HspB2 genes.
2002,
Pubmed
Takai,
Origins of bidirectional promoters: computational analyses of intergenic distance in the human genome.
2004,
Pubmed
Wasserman,
Human-mouse genome comparisons to locate regulatory sites.
2000,
Pubmed
Wistow,
The duck gene for alpha B-crystallin shows evolutionary conservation of discrete promoter elements but lacks heat and osmotic shock response.
1995,
Pubmed
Wray,
The evolution of transcriptional regulation in eukaryotes.
2003,
Pubmed
Yoshida,
Head-to-head juxtaposition of Fas-associated phosphatase-1 (FAP-1) and c-Jun NH2-terminal kinase 3 (JNK3) genes: genomic structure and seven polymorphisms of the FAP-1 gene.
2002,
Pubmed
Zhang,
Characterization of the bidirectional promoter region between the human genes encoding VLCAD and PSD-95.
2003,
Pubmed
Zhu,
Bayesian adaptive sequence alignment algorithms.
1998,
Pubmed
