CRISPR/Cas9-mediated SNAC9 mutants reveal the positive regulation of tomato ripening by SNAC9 and the mechanism of carotenoid metabolism regulation

NAC transcriptional regulators are crucial for tomato ripening.Virus-induced gene silencing(VIGS)of SNAC9(SlNAC19,Gene ID:101248665)affects tomato ripening,and SNAC9 is involved in ethylene and abscisic acid(ABA)metabolic pathways.However,the function of SNAC9 in pigment metabolism in tomatoes remains unclear.This work seeks to discover the mechanism of SNAC9 involvement in pigment metabolism during tomato ripening by establishing a SNAC9 knockout model using CRISPR/Cas9 technology.The results indicated that fruit ripening was delayed in knockout(KO)mutants,and SNAC9 mutation significantly affected carotenoid metabolism.The chlorophyll(Chl)degradation rate,total carotenoid content,and lycopene content decreased significantly in the mutants.The transformation rate of chloroplasts to chromoplasts in mutants was slower,which was related to the carotenoid content.Furthermore,SNAC9 changed the expression of critical genes(PSY1,PDS,CRTISO,Z-ISO,SGR1,DXS2,LCYE,LCYB,and CrtR-b2)involved in pigment metabolism in tomato ripening.SNAC9 knockout also altered the expression levels of critical genes involved in the biosynthesis of ethylene and ABA.Accordingly,SNAC9 regulated carotenoid metabolism by directly regulating PSY1,DXS2,SGR1,and CrtR-b2.This research provides a foundation for developing the tomato ripening network and precise tomato ripening regulation.

DualFace:Two-stage drawing guidance for freehand portrait sketching

Special skills are required in portrait painting, such as imagining geometric structures and facial detail for final portrait designs. This makes it a difficult task for users, especially novices without prior artistic training, to draw freehand portraits with high-quality details. In this paper, we propose dualFace, a portrait drawing interface to assist users with different levels of drawing skills to complete recognizable and authentic face sketches. Inspired by traditional artist workflows for portrait drawing, dualFace gives two-stages of drawing assistance to provide global and local visual guidance. The former helps users draw contour lines for portraits (i.e., geometric structure), and the latter helps users draw details of facial parts, which conform to the user-drawn contour lines. In the global guidance stage, the user draws several contour lines, and dualFace then searches for several relevant images from an internal database and displays the suggested face contour lines on the background of the canvas. In the local guidance stage, we synthesize detailed portrait images with a deep generative model from user-drawn contour lines, and then use the synthesized results as detailed drawing guidance. We conducted a user study to verify the effectiveness of dualFace, which confirms that dualFace significantly helps users to produce a detailed portrait sketch.

RNA m^(6)A Modification in Cancers: Molecular Mechanisms and Potential Clinical Applications

N^(6)-Methyladenosine(m^(6)A)RNA modification brings a new dawn for RNA modification researches in recent years.This posttranscriptional RNA modification is dynamic and reversible,and is regulated by methylases(“writers”),demethylases(“erasers”),and proteins that preferentially recognize m^(6)A modifications(“readers”).The change of RNA m^(6)A modification regulates RNA metabolism in eucaryon,including translation,splicing,exporting,decay,and processing.Thereby the dysregulation ofm^(6)A may lead to tumorigenesis and progression.Given the tumorigenic role of abnormalm^(6)A expression,m^(6)A regulators may function as potential clinical therapeutic targets for cancers.In this review,we emphasize on the underlying mechanisms of m^(6)A modifications in tumorigenesis and further introduce the potential m^(6)A regulators-associated therapeutic targets for tumor therapy.