| First Author | Chui DH | Year | 1977 |
| Journal | Blood | Volume | 50 |
| Issue | Suppl 1 | Pages | 104 (Abstr.) |
| Mgi Jnum | J:30711 | Mgi Id | MGI:78283 |
| Citation | Chui DH, et al. (1977) Unequal alpha and beta globin mRNA in reticulocytes of normal and mutant (f/f) fetal mice. Blood 50(Suppl 1):104 (Abstr.) |
| abstractText | Full text of Abstract. UNEQUAL alpha AND Beta GLOBIN mRNA IN RETICULOCYTES OF NORMAL AND MUTANT f/f FETAL MICE. D.H.K. Chui, M. Patterson*, and S.T. Bayley*. McMaster University, Hamilton, Ontario, Canada. Mice carrying two mutant genes at the f locus on chromosome 13 have severe hypochromic and microcytic anemia durina fetal development. Beta globin chain synthesis is decreased compared to alpha globin chain synthesis in mutant (f/f) fetal reticulocytes (Blood 50:165, 1977). Globin chain synthesis is balanced in normal (+/+) fetal reticulocytes. This study was undertaken to determine the relative amounts of functional alpha and Beta globin mRNA in +/+Cellular RNA was extracted from +/+ and f/f fetal reticulocytes. Cellular RNA was extracted from +/+ and f/f day 18 fetal reticulocytes as well from reticulocytes of normal adult mice treated with phenylhydra-zine. mRNA was isolated by poly-U sepharose affinity chromatography, and translated in a wheat germ cell free system containing 2 mM Mg++, 80 mM K+, as well as spermine and spermidine. The product was analysed by CMC-urea column chromatography. mRNA from adult reticulocytes directs synthesis of equal amounts of alpha and Beta globin chains (alpha/Beta = 1.10 +/- 0.03). mRNA from either +/+ or f/f fetal reticulocytes directs synthesis of much more alpha than Beta globin chains (alpha/Beta = 1.44 +/- 0.05 for +/+ and 1.49 +/- 0.06 for f/f). With much more input of either adult or fetal reticulocyte mRNA to the cell free system, alpha chain synthesis is preferentially decreased compared to Beta chain synthesis and the alpha/Beta synthetic ratio is markedly reduced. These data indicate that in fetal mouse reticulocytes, there are much more alpha than Beta globin mRNA, and that there must be translational regulatory mechanisms to bring about equal synthesis of alpha and Beta globin chains in intact, normal fetal reticulocytes. In mutant f/f reticulocytes, these regulatory mechanisms are deranged, leading to unbalanced globin chain production. |
