Motivation: The CRISPR-Cas system is an adaptive immune system in many archaea and bacteria, which provides resistance against invading genetic elements. The first phase of CRISPR-Cas immunity is called adaptation, in which small DNA fragments are excised from genetic elements and are inserted into a CRISPR array generally adjacent to its so called leader sequence at one end of the array. It has been shown that transcription initiation and adaptation signals of the CRISPR array are located within the leader. However, apart from promoters, there is very little knowledge of sequence or structural motifs or their possible functions. Leader properties have mainly been characterized through transcriptional initiation data from single organisms but large-scale characterization of leaders has remained challenging due to their low level of sequence conservation.
Results: We developed a method to successfully detect leader sequences by focusing on the consensus repeat of the adjacent CRISPR array and weak upstream conservation signals. We applied our tool to the analysis of a comprehensive genomic database and identified several characteristic properties of leader sequences specific to archaea and bacteria, ranging from distinctive sizes to preferential indel localization. CRISPRleader provides a full annotation of the CRISPR array, its strand orientation as well as conserved core leader boundaries that can be uploaded to any genome browser. In addition, it outputs reader-friendly HTML pages for conserved leader clusters from our database.
Availability And Implementation: CRISPRleader and multiple sequence alignments for all 195 leader clusters are available at http://www.bioinf.uni-freiburg.de/Software/CRISPRleader/
Contact: costa@informatik.uni-freiburg.de or backofen@informatik.uni-freiburg.de
Supplementary Information: Supplementary data are available at Bioinformatics online.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1093/bioinformatics/btw454 | DOI Listing |
Cell Prolif
December 2024
Department of Interventional Radiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
The recent advancements in cancer immunotherapy have spotlighted the potential of natural killer (NK) cells, particularly chimeric antigen receptor (CAR)-transduced NK cells. These cells, pivotal in innate immunity, offer a rapid and potent response against cancer cells and pathogens without the need for prior sensitization or recognition of peptide antigens. Although NK cell genetic modification is evolving, the viral transduction method continues to be inefficient and fraught with risks, often resulting in cytotoxic outcomes and the possibility of insertional mutagenesis.
View Article and Find Full Text PDFCurr Issues Mol Biol
December 2024
Embrapa Mandioca e Fruticultura, Cruz das Almas 44380-000, BA, Brazil.
Bananas and plantains are important staple food crops affected by biotic and abiotic stresses. The gene editing technique via Clustered Regularly Interspaced Short Palindromic Repeats associated with the Cas protein (CRISPR/Cas) has been used as an important tool for development of cultivars with high tolerance to stresses. This study sought to develop a protocol for the construction of vectors for gene knockout.
View Article and Find Full Text PDFBiosensors (Basel)
December 2024
Key Laboratory of Microbiological Metrology, Measurement & Bio-product Quality Security, State Administration for Market Regulation, College of Life Science, China Jiliang University, Hangzhou 310018, China.
Antibiotics, celebrated as some of the most significant pharmaceutical breakthroughs in medical history, are capable of eliminating or inhibiting bacterial growth, offering a primary defense against a wide array of bacterial infections. However, the rise in antimicrobial resistance (AMR), driven by the widespread use of antibiotics, has evolved into a widespread and ominous threat to global public health. Thus, the creation of efficient methods for detecting resistance genes and antibiotics is imperative for ensuring food safety and safeguarding human health.
View Article and Find Full Text PDFNucleic Acids Res
December 2024
Gladstone Institute of Data Science and Biotechnology, 1650 Owens St, San Francisco, CA 94158, USA.
The CRISPR integrases Cas1-Cas2 create immunological memories of viral infection by storing phage-derived DNA in CRISPR arrays, a process known as CRISPR adaptation. A number of host factors have been shown to influence adaptation, but the full pathway from infection to a fully integrated, phage-derived sequences in the array remains incomplete. Here, we deploy a new CRISPRi-based screen to identify putative host factors that participate in CRISPR adaptation in the Escherichia coli Type I-E system.
View Article and Find Full Text PDFFront Genome Ed
December 2024
Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden.
CRISPR-Cas (Clustered Regularly Interspaced Short Palindromic Repeats-CRISPR-associated proteins) has undergone marked advancements since its discovery as an adaptive immune system in bacteria and archaea, emerged as a potent gene-editing tool after the successful engineering of its synthetic guide RNA (sgRNA) toward the targeting of specific DNA sequences with high accuracy. Besides its DNA editing ability, further-developed Cas variants can also edit the epigenome, rendering the CRISPR-Cas system a versatile tool for genome and epigenome manipulation and a pioneering force in precision medicine. This review explores the latest advancements in CRISPR-Cas technology and its therapeutic and biomedical applications, highlighting its transformative impact on precision medicine.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!