Small regulatory RNAs are a class of non-coding RNAs that function primarily as negative regulators of other RNA transcripts. The principal members of this class are microRNAs and siRNAs, which are involved in post-transcriptional gene silencing. These small RNAs, which in their functional form are singlestranded and ~22 nucleotides in length, guide a gene silencing complex to an mRNA by comple...

Over the last decade, RNA interference pathways have emerged in eukaryotes as critical regulators of many diverse biological functions including, among others, transcriptional gene regulation, post-transcriptional gene silencing, heterochromatin remodelling, suppression of transposon activity, and antiviral defences. Although this gene silencing process has been reported to be relatively well c...

Virus-induced gene silencing (VIGS) can be harnessed to sequence-specifically degrade host transcripts and induce heritable epigenetic modifications referred as virus-induced post-transcriptional (ViPTGS) transcriptional (ViTGS), respectively. Both ViPTGS ViTGS enable manipulation of endogenous expression without the need for transgenesis. Although VIGS has been widely used in many plant specie...

Abstract Tomato yellow leaf curl virus (TYLCV) is known to encode 6 canonical viral proteins. Our recent study revealed that TYLCV also encodes some additional small proteins with potential virulence functions. The fifth ORF of in the complementary sense, which we name C5, evolutionarily conserved, but little about its expression and function during infection. Here, confirmed C5 by analyzing pr...

Sex chromosomes are uniquely subject to chromosome-wide silencing during male meiosis, and silencing persists into post-meiotic spermatids. Against this background, a select set of sex chromosome-linked genes escapes silencing and is activated in post-meiotic spermatids. Here, we identify a novel mechanism that regulates escape gene activation in an environment of chromosome-wide silencing in m...

During meiosis, homologous chromosomes must pair in order to permit recombination and correct chromosome segregation to occur. Two recent papers show that meiotic pairing is also important for correct gene expression during meiosis. They describe data for the filamentous fungus Neurospora crassa that show that a lack of pairing generated by ectopic integration of genes can result in silencing o...

Synthetic biology has potential spaceflight applications yet few if any studies have attempted to translate Earth-based synthetic tools into spaceflight. An exogenously inducible biological circuit for protein production in Arabidopsis thaliana , pX7-AtPDSi (Guo et al. 2003), was flown ISS and functionally investigated. Seedlings were grown a custom built 1.25 U plant greenhouse. Images recorde...