Not Only Editing: A Cas-Cade of CRISPR/Cas-Based Tools for Functional Genomics in Plants and Animals.

The advent of CRISPR/Cas9 technology has revolutionized genome editing, enabling the attainment of once-unimaginable goals. CRISPR/Cas's groundbreaking attributes lie in its simplicity, versatility, universality, and independence from customized DNA-protein systems, erasing the need for specialized expertise and broadening its scope of applications. It is therefore more and more used for genome modification including the generation of mutants. Beyond such editing scopes, the recent development of novel or modified Cas-based systems has spawned an array of additional biotechnological tools, empowering both fundamental and applied research. Precisely targeting DNA or RNA sequences, the CRISPR/Cas system has been harnessed in fields as diverse as gene regulation, deepening insights into gene expression, epigenetic changes, genome spatial organization, and chromatin dynamics. Furthermore, it aids in genome imaging and sequencing, as well as effective identification and countering of viral pathogens in plants and animals. All in all, the non-editing aspect of CRISPR/Cas exhibits tremendous potential across diverse domains, including diagnostics, biotechnology, and fundamental research. This article reviews and critically evaluates the primary CRISPR/Cas-based tools developed for plants and animals, underlining their transformative impact.

Lipidome remodeling in response to nutrient replenishment requires the tRNA modifier Deg1/Pus3 in yeast.

In the yeast Saccharomyces cerevisiae, the absence of the pseudouridine synthase Pus3/Deg1, which modifies tRNA positions 38 and 39, results in increased lipid droplet (LD) content and translational defects. In addition, starvation-like transcriptome alterations and induced protein aggregation were observed. In this study, we show that the deg1 mutant increases specific misreading errors. This could lead to altered expression of the main regulators of neutral lipid synthesis which are the acetyl-CoA carboxylase (Acc1), an enzyme that catalyzes a key step in fatty acid synthesis, and its regulator, the Snf1/AMPK kinase. We demonstrate that upregulation of the neutral lipid content of LD in the deg1 mutant is achieved by a mechanism operating in parallel to the known Snf1/AMPK kinase-dependent phosphoregulation of Acc1. While in wild-type cells removal of the regulatory phosphorylation site (Ser-1157) in Acc1 results in strong upregulation of triacylglycerol (TG), but not steryl esters (SE), the deg1 mutation more specifically upregulates SE levels. In order to elucidate if other lipid species are affected, we compared the lipidomes of wild type and deg1 mutants, revealing multiple altered lipid species. In particular, in the exponential phase of growth, the deg1 mutant shows a reduction in the pool of phospholipids, indicating a compromised capacity to mobilize acyl-CoA from storage lipids. We conclude that Deg1 plays a key role in the coordination of lipid storage and mobilization, which in turn influences lipid homeostasis. The lipidomic effects in the deg1 mutant may be indirect outcomes of the activation of various stress responses resulting from protein aggregation.