The plant genus Lycium (Solanaceae) originated in the Americas and includes approximately 85 species that are distributed worldwide. The vast majority of Old World species occur in southern Africa and eastern Asia. In this study, we examine biogeographic relationships among Old World species using a phylogenetic approach coupled with molecular evolutionary analyses of the S-RNase self-incompati...

The Bacillus subtilis RNase M5 complex, responsible for the terminal maturation of 5 S rRNA, includes two proteins. One of these proteins is ribosomal protein BL16 (equivalent to Escherichia coli EL18); the other, the alpha component, is required for catalysis. The RNase M5 alpha component has been purified in bulk extensively, and the active polypeptide (Mr approximately 24,000) identified fol...

Tetraploid sour cherry (Prunus cerasus L.) exhibits gametophytic self-incompatibility (GSI) whereby the specificity of self-pollen rejection is controlled by alleles of the stylar and pollen specificity genes, S-RNase and SFB (S haplotype-specific F-box protein gene), respectively. As sour cherry selections can be either self-compatible (SC) or self-incompatible (SI), polyploidy per se does not...

In cultures of certain streptococcal strains, RNA added as a carrier for streptolysin S (SLS) was hardly degraded, owing to deficiency of extracellular RNase activity. Production of RNA-SLS into culture supernatant was markedly reduced in the RNase-deficient streptococci. Even in these RNase-less strains, guanylic-acid rich oligonucleotides, polyG or trypan blue effectively induced SLS producti...

Because of their sessile lifestyle, plants have developed extensive mechanisms to safeguard their genetic information from one generation to the next. The WEE1 kinase is one of the guardians of genome integrity, being important during S-phase progression under replication stress. Knock-out plants for WEE1 (WEE1(KO)) show a hypersensitive response when grown on replication-inhibiting drugs. Rece...

Small cytoplasmic RNA (scRNA) of Bacillus subtilis is the RNA component of the signal recognition particle. scRNA is transcribed as a 354-nt precursor, which is processed to the mature 271-nt scRNA. Previous work demonstrated the involvement of the RNase III-like endoribonuclease, Bs-RNase III, in scRNA processing. Bs-RNase III was found to cleave precursor scRNA at two sites (the 5' and 3' cle...

Regnase-1 is an RNase that directly cleaves mRNAs of inflammatory genes such as IL-6 and IL-12p40, and negatively regulates cellular inflammatory responses. Here, we report the structures of four domains of Regnase-1 from Mus musculus-the N-terminal domain (NTD), PilT N-terminus like (PIN) domain, zinc finger (ZF) domain and C-terminal domain (CTD). The PIN domain harbors the RNase catalytic ce...

Substrate recognition and cleavage by the bacterial RNase P RNA requires two domains, a specificity domain, or S-domain, and a catalytic domain, or C-domain. The S-domain binds the T stem-loop region in a pre-tRNA substrate to confer specificity for tRNA substrates. In this work, the entire S-domain of the Bacillus subtilis RNase P RNA is replaced with an artificial substrate binding module. Ne...

RNase III enzymes cleave double stranded (ds)RNA. This is an essential step for regulating the processing of mRNA, rRNA, snoRNA and other small RNAs, including siRNA and miRNA. Arabidopsis thaliana encodes nine RNase III: four DICER-LIKE (DCL) and five RNASE THREE LIKE (RTL). To better understand the molecular functions of RNase III in plants we developed a biochemical assay using RTL1 as a mod...

Hepatitis C virus (HCV) RNA is recognized and cleaved in vitro by RNase P enzyme near the AUG start codon. Because RNase P identifies transfer RNA (tRNA) precursors, it has been proposed that HCV RNA adopts structural similarities to tRNA. Here, we present experimental evidence of RNase P sensitivity conservation in natural RNA variant sequences, including a mutant sequence (A368-G) selected in...