Identification and expression of Helios, a member of the Ikaros family, in the Mexican axolotl: implications for the embryonic origin of lymphocyte progenitors
| Autor: | Charles Durand, Jacques Charlemagne, Julien S. Fellah, Fabienne Kerfourn |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Immunology
Molecular Sequence Data HeliOS Axolotl Immunology and Allergy Animals Lymphopoiesis Blood islands Amino Acid Sequence Lymphocytes RNA Messenger Cloning Molecular biology biology.organism_classification Hematopoietic Stem Cells Embryonic stem cell Cell biology Hematopoiesis Ambystoma mexicanum DNA-Binding Proteins Haematopoiesis Neurula Female Stem cell Sequence Alignment Transcription Factors |
| Zdroj: | European journal of immunology. 32(6) |
| ISSN: | 0014-2980 |
| Popis: | 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. |
| Databáze: | OpenAIRE |
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