Identification and expression of Helios, a member of the Ikaros family, in the Mexican axolotl: implications for the embryonic origin of lymphocyte progenitors.
Eur J Immunol
; 32(6): 1748-52, 2002 Jun.
Article
em En
| MEDLINE
| ID: mdl-12115658
Transcription factors of the Ikaros gene family are critical for the differentiation of T and B lymphocytes from pluripotent hematopoietic stem cells. To study the first steps of lymphopoiesis in the Mexican axolotl, we have cloned the Helios ortholog in this urodele amphibian species. We demonstrated that the axolotl Helios contains a 144-bp deletion at the 5' end of the activation domain. Helios is expressed in both the thymus and spleen but not in the liver of the pre-adult axolotl. During ontogeny, Helios transcripts are detected from neurula stage, before the apparition of the first Ikaros transcripts and the colonization of lymphoid tissues. Interestingly, Helios and Ikaros mRNA are found predominantly in the ventral blood islands of late tail-bud embryos. These results suggest that in contrast to the Xenopus and amniote embryos where two sites of hematopoiesis have been characterized, the ventral blood islands could be the major site of hematopoiesis in the axolotl.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fatores de Transcrição
/
Linfócitos
/
Proteínas de Ligação a DNA
/
Ambystoma mexicanum
/
Hematopoese
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Limite:
Animals
País/Região como assunto:
Mexico
Idioma:
En
Revista:
Eur J Immunol
Ano de publicação:
2002
Tipo de documento:
Article
País de afiliação:
França
País de publicação:
Alemanha