N 6 -methyladenosine (m 6 A) on RNA and its regulatory components play critical roles in various developmental processes in mammals. However, the landscape and function of m 6 A in early embryos remain unclear due to limited materials. Current methods typically need total RNA greater than microgram amount to map m 6 A positions, which prevents us from revealing the crucial role of m 6 A in early embryonic development in mice. Here, we developed an ultra-low-input(ULI) MeRIP-seq method to reveal the transcriptome-wide m 6 A landscape in limited biological materials which contain as low as 50ng total RNA. Antibody-based ULI MeRIP-seq reveal the high e ciency of immunoprecipitation and reduced RNA loss during the experiments. Sequencing data reveal the m 6 A enrichment of mRNAs as well as noncoding RNAs which are highly recapitulated the results generated by 2µg of total RNA.To further promote the application on limited RNA materials, we describe a step-by-step protocol about how to construct a successful ULI MeRIP-seq library.

Ac oncise,s calable,s ix-step (longest linear sequence) synthetic route to ovatodiolide scaffolds was developed for the first time.T his protecting-group-free route features tandem ring-opening metathesis/ring-closing metathesis reactions to install the macrocycle-fused butenolide ring and at andem allylboration/lactonization to build the amethylene-g-lactone.Our syntheses have enabled the determination of the hitherto unknown stereochemical configurations of this family of natural products.P reliminary tests of structure-activity relationships were conducted with four natural ovatodiolides and three analogues.F urther assays indicated that the synthetic natural product isoovatodiolide can significantly decrease the population of hepatic cancer stem cells and reduce the tumorsphere-forming capability of HepG2 cells.

Ac oncise,s calable,s ix-step (longest linear sequence) synthetic route to ovatodiolide scaffolds was developed for the first time.T his protecting-group-free route features tandem ring-opening metathesis/ring-closing metathesis reactions to install the macrocycle-fused butenolide ring and at andem allylboration/lactonization to build the amethylene-g-lactone.Our syntheses have enabled the determination of the hitherto unknown stereochemical configurations of this family of natural products.P reliminary tests of structure-activity relationships were conducted with four natural ovatodiolides and three analogues.F urther assays indicated that the synthetic natural product isoovatodiolide can significantly decrease the population of hepatic cancer stem cells and reduce the tumorsphere-forming capability of HepG2 cells.

Stepwise modification of ovatodiolide revealed a prodrug, NMP-diepoxyovatodiolide which can provide sustained release of an active compound, substantial metabolic stability and a unique accumulation profile in the liver. Besides, NMP-diepoxyovatodiolide...