Recent advances of the biological and biomedical applications of CRISPR/Cas systems

Abstract

It has also been reported that about 40% of spacers from lactic acid bacteria, namely Streptococcus thermophiles, have a homologue corresponding to either phage or plasmid DNA sequences among the isolated and sequenced phage's genome [3]. Thus, the spacers are proposed to be derived from foreign DNA including phage and plasmids. Bacteria generally acquire new spacers once they are exposed to new viruses in order to confer resistance to the cognate virus. Therefore, spacers present in a certain bacterium typically reveal the historical record of phages that the bacterium has been exposed to [4]. The leader sequence is commonly located 5' to the CRISPR locus and is rich in AT nucleotides. However, it has been demonstrated that the leader sequence is incapable of encoding RNAs or proteins, and that it is located next to the short repeats. Apart from the leader sequence, the genes encoding Cas proteins are found to be localized either upstream or downstream of the CRISPR locus.The CRISPR/Cas system is postulated to be formed in three stages. In the adaption stage, bacterial cells acquire sequences derived from foreign DNA such as viral DNA, and then incorporate them into the bacterial CRISPR array. During the expression stage, precursor CRISPR RNA (crRNA)

Application of CRISPR/Cas13a-based biosensors in serum marker detection

“…The interference phase is when the Cas protein-crRNA complex targets the recognition, cleavage, and inactivation of foreign DNA or RNA. [5][6][7]9,10 The classication of CRISPR/Cas systems is mainly based on differences in Cas protein composition and sequence differences between effector modules, [5][6][7]10 and all Cas proteins can be divided into four functional classes: nucleases and/or recombinases, which participate in spacer acquisition; RNases, which catalyze crRNA-guided processing and binds to mature crRNA to form stable crRNP complexes for targeted surveillance proteins; nucleases, which are responsible for degrading the DNA or RNA target. 5,9 The CRISPR/Cas system is currently mainly divided into 2 classes.…”

Developing algae as a sustainable food source

“…CRISPR technology utilizes machinery that was originally identified as a defense mechanism for bacteria against viral pathogens ( 143 ). This system has been modified as a method for precise genetic modifications, and a broad range of CRISPR/Cas-associated proteins have been discovered as this system continues to be characterized ( 144 ). CRISPR technology has been applied to algae and makes site-directed genetic modifications possible within these diverse organisms.…”

CRISPR/Cas9 Mediated Therapeutic Approach in Huntington’s Disease

“…CRISPR/Cas 9 genome editing technology allows editing the genome of stem cells using modified stem cells as regenerative drugs in therapeutic applications [ 51 ]. The CRISPR/Cas 9 system is also used for live cell imaging of genomic loci and for monitoring RNA in living cells [ 52 ].…”