RNase III proteins play key roles in microRNA (miRNA) biogenesis. The nuclear RNase III Drosha cleaves primary miRNAs (pri-miRNAs) to release hairpin-shaped pre-miRNAs that are subsequently cut by the cytoplasmic RNase III Dicer to generate mature miRNAs. While Dicer (class III) and other simple

expression in various single, double, and triple maturation mutants, we have identified multiple regulatory links among all four genes. We found that one of the major roles of LEC2 was to upregulate FUS3 and ABI3. The lec2 mutation is responsible for a dramatic decrease in ABI3 and FUS3 expression, and most

that this maturation event is linked to the maturation cleavage of the virion proteins, which is catalyzed by the viral protease (PR). We found that the dimeric RNA isolated from PR- mutant virions resembles that from immature virions: it has a lower electrophoretic mobility and a lower sedimentation rate, and it also

predominant haplotype associated with the N51I+C59R+S108N triple-mutant dhfr allele has been reported recently in 4 African countries. A more comprehensive picture of the evolution of this mutant allele in Africa is lacking. Methods. Seventy-five P. falciparum isolates carrying the wild-type dhfr allele

Experiments were performed with mature embryos of four rice mutants for in vitro callus induction and plant regeneration. Different concentrations of 2,4-D and BAP combined, Kn and NAA combined and MET were used to assess their effects on induction of callus, shoot and roots. Given concentrations

plasmids; Z. Chen (Purdue University) for providing Arabidopsis wrky single and triple mutants; and E. Schmelzer, E. Logemann, A. Reinstaedler, M. Hallstein, and H. Häweker for technical support. This work was supported by funds from the Max Planck Society, a Deutsche Forschungsgemeinschaft grant

Vaccine protection by a triple deletion mutant

the maturation pathway. This Raman study represents the first detailed doi:10.1006/jmbi.2001.4476 available online at

immature cells of one wild-type and two early mature mutant clones into mature cells of wild-type. The proportion of immature cells brought about by the injection increased until about 10-15 fissions after conjugation of the donor cells in all three clones. But the percentage of immature cells induced

delivery to the vacuole, the amino-terminal propeptide is removed by proteinase B (PrB) to yield the mature 50-kD hydrolase. We exploited this delivery-dependent maturation event in a mutant screen to identify genes whose products are involved in API targeting. Using antiserum to the API propeptide, we