Skip to main content

Posts

Showing posts from August, 2019

CRISPR can now be used as a drug delivery molecule.

Drugs (or any molecules) could be delivered to the target site and released under the control of CRISPR 12a.

James Collins, MIT, Cambridge used CRISPR  to deliver drug molecules. They used water-filled polymers that are held together by strands of DNA, known as DNA hydrogels. To alter the properties of these materials, Collins's team used a form of CRISPR called Cas12a. (The gene-editor CRISPR–Cas9 uses the Cas9 enzyme to snip a DNA sequence at the desired point.) The Cas12a enzyme can be programmed to recognize a specific DNA sequence. The enzyme cuts its target DNA strand, then severs single strands of DNA nearby.
This property allowed the researchers to build a series of CRISPR-controlled hydrogels containing a target DNA sequence and single strands of DNA, which breaks up after Cas12a recognizes the target sequence in a stimulus. The break-up of the single DNA strands triggers the hydrogels to change shape or, in some cases, completely dissolve, releasing a payload. The team cre…

RNA editing, CRISPR-Cas 13 provides herd immunity against dsDNA phage.

CRISPR-cas13: the only RNA editing CRISPR till date. RNA targeting CRISPR-cas13 provides immunity against dsDNA phage without cutting the genome, unlike the other 5 types which work by cutting the genome. CRISPR-Cas13 works differently.  It provides herd immunity to the bacteria.
There are six types of CRISPR in literature till now (1-6).
CRISPR Cas VI is the only one that cuts the RNA. It cuts the RNA transcript complementary to the target sequence of the mRNA. After cutting the complementary RNA, it starts cutting all other mRNAs of the phage which Scientists called Collateral damage. This is the phenomena that provide Herd immunity.
References: Cas13 Helps Bacteria Play Dead when the Enemy Strikes. Cell Host and Microbe. https://doi.org/10.1016/j.chom.2019.06.012
Follow and like Layman's Biology Facebook page for more news