Journal: Synthetic and Systems Biotechnology

Article Title: Functional characterization of four glycosyltransferases for biosynthesis of steroidal saponins in medicinal plant Paris polyphylla

doi: 10.1016/j.synbio.2026.04.002

Figure Lengend Snippet: Reaction schemes and LC-MS analysis of Pp UGTs reactions with diosgenin and pennogenin . ( a ) Biosynthesis of trillin mediated by UGT91BP2 and UGT703R1–3 through transferring glucose from UDP-glucose to the C-3 OH position of diosgenin. ( b ) Extracted ion chromatograms (EICs) of the in vitro enzyme activity assays of recombinant UGT91BP2 and UGT703R1–3 with UDP-glucose and diosgenin showing the formation of trillin, as compared to the authentic trillin standard. Control is the empty expression vector. ( c ) MS spectra of the enzymatic reaction products in hydrogen and sodium ion adducts compared to the fragmentation pattern of the trillin standard. The product molecular ions [M + H] + and [M +Na] + and the feature fragment ion [M + H − Glc] + with m / z 415.32 are marked. Of note, additional peaks observed in the diosgenin EIC ( m / z 415.32) for UGT703R1–3 might correspond to substrate isomeric impurities, in-source adducts, or minor non-enzymatic by-products; these peaks, which arose from the extracted ion flow of the substrate m / z , did not co-elute with the product, trillin , and therefore did not affect the interpretation of the product formation. ( d ) Biosynthesis of pennogenin 3- O -glucoside mediated by the UGT703R1–3 through transferring glucose from UDP-glucose to the C-3 OH position of pennogenin. ( e ) EICs of the in vitro enzyme activity assays of recombinant UGT91BP2 and UGT703R1–3 with UDP-glucose and pennogenin showing the formation of pennogenin 3- O -glucoside, compared to the control empty expression vector. ( f ) MS/MS spectra ([M + H – Glc] + and [M + H – Glc − H 2 O] + ) of the enzymatic reaction products.

Article Snippet: Diosgenin, pennogenin, and trillin standard compounds were purchased from Chengdu Push Biotechnology Co., Ltd., and Shanghai Yuanye Biotechnology Co., Ltd. (China).

Techniques: Liquid Chromatography with Mass Spectroscopy, Transferring, In Vitro, Activity Assay, Recombinant, Control, Expressing, Plasmid Preparation, Tandem Mass Spectroscopy

Journal: Synthetic and Systems Biotechnology

Article Title: Functional characterization of four glycosyltransferases for biosynthesis of steroidal saponins in medicinal plant Paris polyphylla

doi: 10.1016/j.synbio.2026.04.002

Figure Lengend Snippet: Transient expression and characterization of Pp UGTs in Nicotiana benthamiana . ( a ) UHPLC-MS traces of the trillin formation in N. benthamiana leaf extracts transiently expressing UGT91BP2 and UGT703R1–3 with the infiltration of diosgenin substrate, compared to trillin authentic standard and empty vector control. Q1: parent ion; Q3: daughter ion. ( b ) Confocal microscopic images of the localization of UGT91BP2-GFP, UGT703R1-GFP, UGT703R2-GFP and UGT703R3-GFP in N. benthamiana leaves. DAPI (a nuclear-specific fluorescence dye) acts as a nucleus indicator. Scale bars, 20 μm. The experiments were repeated two times with similar results.

Article Snippet: Diosgenin, pennogenin, and trillin standard compounds were purchased from Chengdu Push Biotechnology Co., Ltd., and Shanghai Yuanye Biotechnology Co., Ltd. (China).

Techniques: Expressing, Plasmid Preparation, Control, Fluorescence

Journal: iScience

Article Title: A key role for the exoribonuclease XRN1 in regulating the hepatitis B viral transcriptome

doi: 10.1016/j.isci.2026.116328

Figure Lengend Snippet: XRN1 regulation of the HBV transcriptome (A) HBV transcript mapping. Cartoon depicting the genomic viral RNA with the 5′ and 3′ epsilon stem loops, canonical transcription start sites, and major viral RNAs along with open reading frames (core, Pol, L, M, S, and X). HepG2-NTCP WT or XRN1 KO22 cells were infected with HBV, RNAs extracted at 6 dpi, and analyzed by long-read sequencing. Read counts for pC, pg, preS1, preS2, S, and X transcripts (left), along with spliced isoforms (right), are shown. Data are presented for 6 independent samples and statistical significance assessed using unpaired t tests (corrected for multiple comparisons, ∗ p < 0.05). (B) In vitro pgRNA digestion by XRN1. Capped-analog modified mRNA was synthesized by in vitro transcription. The capped and decapped pgRNA was incubated with XRN1, evaluated by agarose gel electrophoresis, and northern blotting using an HBV probe. Please see also .

Article Snippet: In vitro pgRNA transcription was performed in a 20 μL final volume using a T7 mScript standard mRNA production system by following the protocol provided by the manufacturer (CellScript), the DNA template was digested with 10 μL of a DNase cocktail containing 10 U of DNase I (NEB), 3 μL 10 X DNase I buffer, 2 μL nuclease-free water and incubated at 37°C for 20 min. After purification of the RNA using RNeasy kit (Qiagen), capping and polyadenylation were performed following Cap1 and Cap0 mRNA protocol described in the user’s manual, and the RNA was again purified using RNeasy kit.

Techniques: Infection, Sequencing, In Vitro, Modification, Synthesized, Incubation, Agarose Gel Electrophoresis, Northern Blot