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[Objective] The present paper aimed to screen, isolate and identify the high-yield lignocellulose-degrading endophytic fungi from Taxillus chinensis (DC.) seeds, and provide technical support for the acquisition of lignocellulose-degrading enzymes with strong capacity and T. chinensis artificial cultivation. [Method] The endophytic fungi of T. chinensis seeds were isolated by conventional tissue separation method. Wheat bran was used as substrate for lignin biomass. The activities of laccase, lignin peroxidase, manganese peroxidase and cellulose degrading enzyme were determined by ABTS method, veratrol method, phenol red method and cellulase (CL) activity detection kit. The strains with strong lignocellulosic degradation ability were screened and their classification status was determined according to morphological characteristics and phylogenetic tree analysis. (Result) Four high-yielding lignocellulosic degrading strains (15H3, 2013, 106 and 10y11) were selected from the 57 strains of endophytic fungi from T. chinensis seeds. Among them, the lignin peroxidase activity of strain 15H3 and the manganese peroxidase activity of strain 2013 reached the peak when cultured in the crude enzyme solution of endophytic fungi from T. chinensis seeds for 11 days, they were 7.14 and 11.69 U/mL, respectively. At 9 days, the laccase activity of strain 106, cellulase activity of strain 2013, the manganese peroxidase activity of strain 10y11 were the highest, which were 57.98,0.32 and 8.56 U/mL, respectively. By morphological observation and molecular biology identification, strain 15H3 and 2013 could be identified as Pestalotiopsis arceuthobii and Coniella pseudogranati, respectively. Strains 106 and 10y11 were identified as Fusarium incarnatum. [Conclusion] The endophytic fungi P. arceuthobii, C. pseudogranati and F. incarnatum with high production of lignocellulosic degrading enzymes were screened and identified from T. chinensis seeds, which could provide theoretical basis for the study of the degradation mechanism of T. chinensis invasion into host cell wall and provide data support for the breeding of T. chinensis. [ABSTRACT FROM AUTHOR]

This work aims to study the expression pattern of the most suitable house-keeping genes in different parts of Uncaria rhynchophylla and the key enzymes genes in the upstream synthesis pathway of U. rhynchophylla indole alkaloids. The root, stem hook, leaf and capulse from U. rhynchophylla were used as experimental materials. The expression stabilities of 12 candidate house-keeping genes（18S, SAM, TUA, TUB, EF-1β, EF-1α, RNA L13, GAPDH, Actin6, PAL, CYP, and cdc73）were evaluated by RT-qPCR, GeNorm, NormFinder, Bestkeeper, △Ct, and RefFinder. The results showed that SAM can be used as the most suitable house-keeping genes for gene expression analysis in U. rhynchophylla. Having SAM as house-keeping gene, 15 key enzyme genes involved in alkaloid biosynthesis upstream pathway, i.e., G8H, 8-HGO, IS, CYP76A26, 7-DLGT, 7-DLH, LAMT, SLS, AS, AnPRT, IGPS, TSA, TSB, TDC, and STR were screened based on the co-expression analysis of“genome + transcriptome + metabolome”, and their expression levels were analyzed. The results showed that the expressions of these genes were consistent with the content trend, indicating that the genes are likely involved in the synthesis of terpenoid indole alkaloids. [ABSTRACT FROM AUTHOR]