The present invention relates to genetically modified cells that are capable of optimal transgene expression by co-expressing a silencing suppressor whilst at the same time are also capable of silencing a gene, such as a naturally occurring gene of the cell. The present invention also relates to methods of producing the modified cells, as well as relates to processes for obtaining a genetically modified cell with a desired property.

Compositions and methods for modulating expression of target nucleic acids using a single strand oligoribonucleotide ss-siRNA compound are disclosed.

The present invention provides an isolated nucleic acid comprising, operably linked to an heterologous transgene, at least two copies of a sequence selected from the group of SEQ ID NO:1, SEQ ID NO:2 and SEQ ID NO:3, said at least two copies being selected independently from one another.

The present disclosure describes compositions of matter comprising a ribonucleoprotein complex comprising a nucleic acid-guided nuclease and a guide RNA, and further comprising and a blocking nucleic acid molecule represented by Formula I, wherein Formula I in the 5′-to-3′ direction comprises: A-(B-L).sub.J-C-M-T-D; wherein A is 0-15 nucleotides in length; B is 4-12 nucleotides in length; L is 3-25 nucleotides in length; J is an integer between 1 and 10; C is 4-15 nucleotides in length; M is 1-25 nucleotides in length or is absent, wherein if M is absent then A-(B-L).sub.J-C and T-D are separate nucleic acid strands; T is 17-135 nucleotides in length and comprises at least 50% sequence complementarity to B and C; D is 0-10 nucleotides in length and comprises at least 50% sequence complementarity to A; and wherein the blocking nucleic acid molecule comprises a sequence complementary to a gRNA.

Biosensors for small molecules can be used in applications that range from metabolic engineering to orthogonal control of transcription. Biosensors are produced based on a ligand-binding domain (LBD) using a method that, in principle, can be applied for any target molecule. The LBD is fused to either a fluorescent protein or a transcriptional activator and is destabilized by mutation such that the fusion accumulates only in cells containing the target ligand. The power of this method is illustrated by developing biosensors for digoxin and progesterone. Addition of ligand to cells expressing a biosensor activates transcription in yeast, mammalian cells and plants, with a dynamic range of up to about 100-fold or more. The biosensors are used to improve the biotransformation of pregnenolone to progesterone in yeast and to regulate CRISPR activity in mammalian cells. This work provides a general methodology to develop biosensors for a broad range of molecules.

Methods for increasing or decreasing Nitrogen (N) uptake/assimilation and/or usage in plants comprising over-expressing or repressing one or more transcription factors that have been identified by evaluating temoporal transcription of the TFs in response to N signaling and validated based on TF perturbation studies in plant cells and plants. Combinations of TFs may be used, where each TF may be independently induced or repressed to achieve a desired increase or decrease in N uptake/assimilation.

This invention relates to nanofibers comprising aptamers, which have increased stability and activity relative to free aptamers. The invention further relates to kill-switch nanofibers which disrupt the aptamer nanofibers. The invention further relates to methods of using the aptamer nanofibers and the kill-switch nanofibers to regulate the activity of extracellular targets recognized by the aptamers.

This invention generally relates to a novel RNA composition and its production method useful for generating and expanding induced pluripotent stem cells (iPS cells; iPSC) as well as adult stem cells (ASC). The RNA composition so defined can be used for producing not only non-transgenic but also tumor-free iPS cells. The defined RNA composition contans at least two types of different RNA constructs; one is “miR-302 precursor RNA (pre-miR-302)” and the other is “RNA-dependent RNA polymerase (RdRp)” mRNA. Both of pre-miR-302 and RdRp mRNA contain highly structured RNA comformations, such as hairpin and stem-loop structures. To produce highly structured RNAs, a novel PCR-IVT methodology has been developed and used with a specially designed RNA polymerase-helicase mixture activity.

The present disclosure relates, according to some embodiments, to compositions, methods, systems, and kits for programmable endonucleolytic cleavage of DNA (e.g., ds DNA). For example, the in vitro activity of an Argonaute (e.g., a mesophilic Argonaute CbAgo from Clostridium butyricum) may be synchronized with DNA strand unwinding activity of a helicase (e.g., a nuclease deficient RecB.sup.exo-C DNA helicase from E. coli) for a rapid and efficient cleavage of double-stranded DNA targets. Enzymatic properties of CbAgo and different aspects of ds DNA cleavage were thoroughly explored by adapting high-throughput capillary electrophoreses technique for monitoring CbAgo cleavage activity in concurrence with RecB.sup.exo-C. The present disclosure shows that in the presence of RecB.sup.exo-C, CbAgo can be programmed with guides to cleave any site of interest localized at up to 10 kb distance from the end of linear ds DNA at 37° C. temperature. CbAgo/RecB.sup.exo-C can be programmed to generate DNA fragments flanked with unique single-stranded extensions suitable for seamless ligation with compatible DNA fragments. The present disclosure relates further the compositions, methods, systems, and kits for PRC-free assembly of linear DNA molecules by using CbAgo/RecB.sup.exo-C programmable DNA endonuclease. The results presented here demonstrate that the combination of CbAgo and RecB.sup.exo-C is currently an efficient mesophilic DNA-guided DNA-cleaving programmable endonuclease which can be used to prepare synthetic biology tools that require or benefit from sequence-specific nicking/cleavage of natural DNA at otherwise inaccessible locations.

Provided herein are engineered Class 2, Type V nucleases and guide RNAs useful for the editing of target nucleic acids. Also provided are methods of making and using such variants to modify nucleic acids.