Cloning,Characterization,and Gene Annotation of Cellulose Synthase Genes from Arabidopsis thaliana

The mechanistic basis of cellulose biosynthesis in plants has gained ground during last decade or so.The isolation of plant cDNA clones encoding cotton homologs of the bacterial cellulose

An improved draft genome sequence of hybrid Populus alba×Populus glandulosa

Populus alba × P.glandulosa clone 84 K,derived from South Korea,is widely cultivated in China and used as a model in the molecular research of woody plants because of hi gh gene transformation efficiency.Here,we combined63-fold coverage Illumina short reads and 126-fold coverage PacBio long reads to assemble the genome.Due to the hi gh heterozygosity level at 2.1% estimated by k-mer analysis,we exploited TrioCanu for genome assembly.The PacBio clean subreads of P.alba × P.glandulosa were separated into two parts according to the similarities,compared with the parental genomes of P.alba and P.glandulosa.The two parts of the subreads were assembled to two sets of subgenomes comprising subgenome A(405.31 Mb,from P.alba)and subgenome G(376.05 Mb,from P.glandulosa) with the contig N50 size of 5.43 Mb and 2.15 Mb,respectively.A high-quality P.alba × P.glandulosa genome assembly was obtained.The genome size was 781.36 Mb with the contig N50 size of 3.66 Mb and the longest contig was 19.47 Mb.In addition,a total of 176.95 Mb(43.7%),152.37 Mb(40.5%)of repetitive elements were identified and a total of 38,701 and 38,449 protein-coding genes were predicted in subgenomes A and G,respectively.For functional annotation,96.98% of subgenome A and 96.96% of subgenome G genes were annotated with public databases.This de novo assembled genome will facilitate systematic and comprehensive study,such as multi-omics analysis,in the model tree P.alba X P.glandulosa.

Discovery of Simple Sequence Repeat Markers through Transcriptome Analysis of Baccaurea motleyana

Baccaurea motleyana(rambai)is underutilized fruits that are native to Malaysia,Indonesia and Thailand.In this study,a total of 54,779 unigenes identified from rambai transcriptome were used for simple sequence repeat(SSR)analysis by MIcroSAtellite(MISA).A total of 20,420 SSRs were found to be distributed within 37.27%of the total number of unigenes.Mononucleotide repeats represented the main type,accounting for 64.04%,followed by trinucleotide repeats(20.28%)and dinucleotide repeats(19.94%).Gene annotation to seven databases has a success ratio of 68.53%(National Center for Biotechnology Information(NCBI)protein sequences),53.68%(NCBI nucleotide sequences),27.43%(Kyoto Encyclopedia of Genes and Genome Ortholog),56.0%(SwissProt),52.44%(Protein family),53.99%(Gene Ontology)and 26.44%(Kluster of Orthologous Group).Further rambai SSRs were randomly selected and validated to B.motleyana(rambai),B.macrocarpa(tampoi),B.polyneura(jentik-jentik),B.ramiflora(pupor)and B.scortechinii(setambun).

Accurate, automatic annotation of peptidases with hotpep-protease

Peptidases are essential for intracellular protein processing,signaling and homeostasis,physiological processes and for digestion of food.Moreover,peptidases are important biotechnological enzymes used in processes such as industrial food processing,leather manufacturing and the washing industry.Identification of peptidases is a crucial step in their characterization but peptidase annotation is not a trivial task due to their large sequence diversity.In the present study short,conserved sequence profiles were generated for all peptidase families with more than four members in the comprehensive Merops peptidase database.The sequence profiles were combined with the Homology to Peptide Pattern(Hotpep)method for automatic annotation of peptidases.This method is a standalone software that annotates protease sequences to Merops family and subgroup and is suitable for large-scale sequence analysis.Compared to the Mammalian Degradome Database Hotpep-protease had an accuracy of 92%and a sensitivity of 96%for annotation of the human degradome.Annotation by commonly used methods(Blast and conserved domains)had an accuracy of 69%and a sensitivity of 78%.For fungal genomes,there were large differences between annotation with Hotpep-protease,Blast-and Hidden Markov Model-based annotation and the Merops annotation,which confirms the difficulty of large-scale peptidase annotation.Manual annotation indicated that Hotpep-protease had a positive prediction rate of 0.90 compared to a positive prediction rate of 0.67 for Blast search.Hence,Hotpep-protease is highly accurate method for fast and accurate annotation of peptidases.

TripletGO: Integrating Transcript Expression Profiles with Protein Homology Inferences for Gene Function Prediction

Gene Ontology(GO)has been widely used to annotate functions of genes and gene products.Here,we proposed a new method,Triplet GO,to deduce GO terms of protein-coding and noncoding genes,through the integration of four complementary pipelines built on transcript expression profile,genetic sequence alignment,protein sequence alignment,and naīve probability.Triplet GO was tested on a large set of 5754 genes from 8 species(human,mouse,Arabidopsis,rat,fly,budding yeast,fission yeast,and nematoda)and 2433 proteins with available expression data from the third Critical Assessment of Protein Function Annotation challenge(CAFA3).Experimental results show that Triplet GO achieves function annotation accuracy significantly beyond the current state-of-the-art approaches.Detailed analyses show that the major advantage of Triplet GO lies in the coupling of a new triplet network-based profiling method with the feature space mapping technique,which can accurately recognize function patterns from transcript expression profiles.Meanwhile,the combination of multiple complementary models,especially those from transcript expression and protein-level alignments,improves the coverage and accuracy of the final GO annotation results.The standalone package and an online server of Triplet GO are freely available at https://zhanggroup.org/Triplet GO/.

The first draft genome assembly and data analysis of the Malaysian mahseer (Tor tambroides)

The Malaysian mahseer(Tor tambroides),one of the most valuable freshwater fish in the world,is mainly targeted for human consumption.The mitogenomic data of this species is available to date,but the genomic information is still lacking.For the first time,we sequenced the whole genome of an adult fish on both Illumina and Nanopore platforms.The hybrid genome assembly had resulted in a sum of 1.23 Gb genomic sequence from the 44,726 contigs found with 44 kb N50 length and BUSCO genome completeness of 87.6%.Four types of SSRs had been detected and identified within the genome with a greater AT abundance than that of GC.Predicted protein sequences had been functionally annotated to public databases,namely GO,KEGG and COG.A maximum likelihood phylogenomic tree containing 52 Actinopterygii species and one Sarcopterygii species as outgroup was constructed,providing first insights into the genome-based evolutionary relationship of T.tambroides with other ray-finned fish.These data are crucial in facilitating the study of population genomics,species identification,morphological variations,and evolutionary biology,which are helpful in the conservation of this species.

Characterization of Leaf Transcriptome in Banksia hookeriana

Abstract Banksia is a significant element in vegetation of southwestern Australia, a biodiversity hotspot with global significance. In particular, Banksia hookeriana represents a species with significant economic and ecological importance in the region. For better conservation and management, we reported an overview of transcriptome of B. hookeriana using RNA-seq and de novo assembly. We have generated a total of 202.7 million reads （18.91 billion of nucleotides） from four leaf sam- ples in four plants of B. hookeriana, and assembled 59,063 unigenes （average size = 1098 bp） through de novo transcriptomc assembly. Among them, 39,686 unigenes were annotated against the Swiss-Prot, Clusters of Orthologous Groups （COG）, and NCBI non-redundant （NR） protein databases. We showed that there was approximately one single nucleotide polymorphism （SNP） per 5.6-7.1 kb in the transcriptome, and the ratio of transitional to transversional polymorphisms was approximately 1.82. We compared unigenes of B. hookeriana to those of Arabidopsis thaliana and Nelumbo nucifera through sequence homology, Gene Ontology （GO） annotation, and KEGG pathway analyses. The comparative analysis revealed that unigenes of B. hookeriana were closely related to those of N. nucifera. B. hookeriana, N. nucifera, and A. thaliana shared similar GO anno- tations but different distributions in KEGG pathways, indicating that B. hookeriana has adapted to dry-Mediterranean type shrublands via regulating expression of specific genes. In total 1927 potential simple sequence repeat （SSR） markers were discovered, which could be used in the genotype and genetic diversity studies of the Banksia genus. Our results provide valuable sequence resource for further study in Banksia.