Partial internal transcribed spacer sequence
(ITS) of Sclerotium cepivorum strain C2, using new ITSKF/ITSKR (underline) and ITSLF/ITSLR (double underline) primers (accession number KR108327.1).
In the crRNA biogenesis phase, CRISPR array is transcribed into precursor CRISPR-RNA (pre-crRNA) followed by maturation to crRNAs, each containing a specific spacer sequence
flanked by short RNA sequences .
DNA cleavage requires perfect complementarity between the sgRNA and 10-12 nucleotides located at the 3' end of the 20-nt spacer sequence
, and this hybrid structure is denominated as the "seed" region [8, 21, 23, 24].
Table 1: Blast analysis summary of the different samples using the nuclear internal transcribed spacer sequence
Internal Spacer Sequence
(ITS) analysis: Primer pair, ITS1/ITS4 amplified the ITS1-5.8S rDNA-ITS4 region of fungal genome and a single compact amplified DNA band of approximately 550 bp sizes was observed on 1 % agarose gel (Fig.
We obtained intergenic spacer sequence
data for 27 of the positive samples; 6 samples were B.
We found that the spacer sequence
remained stable over the [approximately equal to]10-year period.
It is characterized by a unique internal transcribed spacer sequence
and causing respiratory tract and disseminated infection in HIV-infected patients in Colombia (1).
Years later, in 1993, the team of researcher Juan Francisco Martinez Mojica of the University of Alicante, Spain, independently reported the same finding but in archaeal genomes, and described the sequences as repetitive and palindromic, which were separated from each other by means of spacer sequences
, and which had a leader sequence at their start (4).