Broyles RH (1999), Use of somatic cell fusion to reprogram globin ...

XB-ART-12549

Semin Cell Dev Biol 1999 Jun 01;103:259-65. doi: 10.1006/scdb.1998.0268.

Show Gene links Show Anatomy links

Use of somatic cell fusion to reprogram globin genes.

Broyles RH .

???displayArticle.abstract???
The developmental phenomenon of hemoglobin switching occurs in all classes of vertebrates and is due to differential regulation of divergent globin genes which are arranged in chromosomally clustered families. By fusing erythroid cells of different developmental programs, it has been shown that erythroid nuclei of either early or late developmental stage can be reprogrammed, i.e. the gene switch can be reversed in adult erythroid nuclei and/or prematurely-induced in fetal/embryonic erythroid nuclei. Experiments with heterokaryons demonstrate that the reprogramming is due to trans-acting factors that are developmental-stage-specific. These results suggest the feasibility of using fusisome-carried sets of nuclear factors to reprogram somatic cells.

???displayArticle.pubmedLink??? 10441537
???displayArticle.link??? Semin Cell Dev Biol

Species referenced: Xenopus laevis
Genes referenced: mtnr1al

???attribute.lit??? ???displayArticles.show???

Figure 1. Experimental design of a heterokaryon experiment using Rana tadpole and adult Xenopus erythroid cells. The erythroid cells of both amphibian species are nucleated at all developmental stages. The heterokaryons express a set of gene products not expressed by either donor cell before fusion, in this case, Rana adult Hb. For clarity, only Rana gene products are shown. Abbreviations: R , Rana tadpole erythrocyte; X , Xenopus adult erythroblast; R Hb, Ta A Rana adult hemoglobin; R Hb, Rana tadpole hemoglobin. Cell fusion protocol: 2=107 cells of T each type were mixed in amphibian Ringer’s and gently pelleted. Fusion was induced by gently stirring the mixed pellet in 0.2 ml of 50% vŽ . rv PEG in amphibian Ringer’s for 30 s at 218C. The PEG was then quickly and gently diluted with 10 vol of a Kq-containg buffer. The cells were incubated at 378C for 5 min and subsequently cultured at 218C in Iscove’s medium amphibian Ž . 28 tonicity for 6 h . Reprinted from ref 32 by permission. Ž .

Figure 2. Photomicrographs of Giemsa-stained preparations after cell fusion. aŽ . Rana tadpole erythroblasts R fused with adult Ž. Ž . t A Xenopus mature erythrocytes X , 30 min after fusion. The round cells with large nuclei are the tadpole erythroblasts R , and the elliptical cells with the Ž .t light cytoplasm and small, dark nuclei are the mature adult erythrocytes X . A R ho- Ž . A t modikaryon arrowhead and groups of R Ž . t A =X heteropolykaryons stars are indicated. b Ž . Ž. Rana tadpole erythrocytes R fused with DMSO-induced MEL adult mouse erythroleukemia cells, 6 Ž . Ž . T h after fusion. The R cells are oval with a light pink cytoplasm and before fusion condensed Ž . T nuclei; the MEL cells are smaller, round, and basophilic stained blue . Note that in the areas of Ž . heterokaryons stars the Ž . Rana tadpole cytoplasm has stained more basophilic, indicating cytoplasmic mixing andror RNA synthesis in the heterokaryons. Barsapprox. 50 mm. See ref 29 for Ž procedures..