Cloning and functional characterisation of avian transcription factor E2A

被引：12

作者：

Conlon T.M. ^{[1
]}

Meyer K.B. ^{[1
]}

机构：

[1] Cambridge Institute for Medical Research, Department of Pathology, University of Cambridge, Cambridge CB2 2XY, WT/MRC Building, Hills Road

来源：

BMC Immunology | / 5卷 / 1期

关键词：

DT40 Cell; Somatic Hypermutation; Class Switch Recombination; bHLH Domain; Smart Race cDNA Amplification;

D O I：

10.1186/1471-2172-5-11

中图分类号：

学科分类号：

摘要：

Background: During B lymphocyte development the E2A gene is a critical regulator of cell proliferation and differentiation. With regards to the immunoglobulin genes the E2A proteins contribute to the regulation of gene rearrangement, expression and class switch recombination. We are now using the chicken cell line DT40 as a model system to further analyse the function of E2A. Results: Here we report the cloning and functional analysis of the transcription factor E2A from chicken. Using RACE PCR on the chicken lymphoma cell line DT40 we have isolated full-length clones for the two E2A splice variants E12 and E47. Sequence conservation between the human and chicken proteins is extensive: the basic-helix-loop-helix DNA binding domain of human and chicken E47 and E12 are 93% and 92% identical, respectively. In addition high levels of conservation are seen in activation domain I, the potential NLS and the ubiquitin ligase interaction domain. E2A is expressed in a variety of tissues in chicken, with higher levels of expression in organs rich in immune cells. We demonstrate that chicken E12 and E47 proteins are strong transcriptional activators whose function depends on the presence of activation domain I. As in mammals, the dominant negative proteins Id1 and Id3 can inhibit the function of chicken E47. Conclusions: The potential for homologous recombination in DT40 allows the genetic dissection of biochemical pathways in somatic cells. With the cloning of avian E2A and the recent description of an in vitro somatic hypermutation assay in this cell line, it should now be possible to dissect the potential role of E2A in the regulation of somatic hypermutation and gene conversion. © 2004 Conlon and Meyer; licensee Biomed Central Ltd.

引用

页数：8

共 26 条

[1]

Bain G., Maandag E.C.R., Izon D.J., Amsen D., Kruisbeek A.M., Weintraub B.C., Krop I., Schlissel M.S., Feeney A.J., van Roon M., van der Valk M., te Rile J.P.J., Berns A., Murre C., E2A proteins are required for proper B cell development and initiation of immunoglobulin gene rearrangements, Cell, 79, pp. 885-892, (1994)

[2]

Zhuang Y., Soriano P., Weintraub H., The helix-loop-helix gene E2A is required for B cell formation, Cell, 79, pp. 875-884, (1994)

[3]

Kee B.L., Quong M.W., Murre C., E2A proteins: Essential regulators at multiple stages of B-cell development, Immunol. Rev., 175, pp. 138-149, (2000)

[4]

Murre C.P., McCaw P.S., Baltimore D., A new DNA binding and dimerization motif in immunoglobulin enhancer binding, daughterless, myoD, and myc proteins, Cell, 56, pp. 777-783, (1989)

[5]

Romanov W.J., Langerak A.W., Goebel P., Wolvers-Tettero I.L.M., van Dongen J.J.M., Feeney A.J., Murre C., E2A and EBF act in synergy with the V(D)J recombinase to generate a diverse immunoglobulin repertoire in nonlymphoid cells, Mol. Cell, 5, pp. 343-353, (2000)

[6]

Quong M.W., Harris D.P., Swain S.L., Murre C., E2A activity is induced dring B-cell activation to promote immunoglobulin class switch recombination, EMBO J., 18, pp. 6307-6318, (1999)

[7]

Sayegh C.E., Quong M.W., Agata Y., Murre C., E-proteins directly regulate expression of activation-induced deaminase in mature B cells, Nat. Immunol., 4, pp. 586-593, (2003)

[8]

Muramatsu M., Kinoshita K., Fagarasan S., Yamada S., Shinkai Y., Honjo T., Class switch recombination and hypermutation require activation-induced cytidine deaminase (AID), a potential RNA editing enzyme, Cell, 102, pp. 553-563, (2000)

[9]

Revy P., Muto T., Levy Y., Geissmann F., Plebani A., Sanal O., Catalan N., Forveille M., Dufourcq-Labelouse R., Gennery A., Tezcan I., Ersoy F., Kayserili H., Ugazio A.G., Brousse N., Muramatsu M., Notarangelo L.D., Kinoshita K., Honjo T., Fischer A., Durandy A., Activation-induced cytidine deaminase (AID) deficiency causes the autosomal recessive form of the Hyper-IgM syndrome (HIGM2), Cell, 102, pp. 565-575, (2000)

[10]

Reynaud C.A., Dahan A., Anquez V., Weill J.C., Somatic hyperconversion diversifies the single Vh gene of the chicken with a high incidence in the D region, Cell, 59, pp. 171-183, (1989)

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