Biology subjects

Peng, D.-H.

Publications and source records attributed to Peng, D.-H..

3 recordsLinked to original sources

bioRxiv2025

Chromosomal-level genome of the Pinus massoniana 'Minlin WY36'

Owing to conifers complex and large genomes, it is challenging to construct a comprehensive reference genome and conduct evolutionary and genomic research. Here, we present the chromosome-level assembly of Pinus massoniana Minlin WY36, a pioneering conifer species used for afforestation, timber production, and oleoresin extraction. The genome size was determined to be 23.41 Gb, with a contig N50 value of 1.15 Mb and a scaffold N50 value of 2.02 Gb. A total of 23.16 Gb of reads (98.93% of the assembled genome) were anchored and oriented onto 12 pseudochromosomes, with chromosome lengths from 1.47 to 2.29 Gb. A total of 32,144 protein-coding genes were predicted, of which 27,173 (84.54%) were functionally annotated. The P. massoniana Minlin WY36 genome consists of 79.41% (18.57 Gb) repetitive sequences, among which long terminal repeat sequences (LTR) were the most abundant. Through comparative genomic analysis, we found that the unique and significantly expanded genes in P. massoniana Minlin WY36 were enriched in the metabolism related to resin synthesis. This study offers valuable insights into conifer evolution and contributes resources for further investigations of conifer adaptation and developmental processes.

genomics↗

bioRxiv2025

Super-giga and tiny orchid genomes illuminate evolution of Orchidaceae

Orchidaceae (orchids) is commonly known as one of the largest families of seed plants, and grow in an extensive range of habitats worldwide. In the present study, we generated chromosome-level reference genomes for two orchids using a combination of PacBio, Illumina, and Hi-C sequencing, Cypripedium singchii has the largest genome and chromosomes among the sequenced species so far, with a genome size of 43.19 Gb (1C) with ten chromosomes, and Apostasia fujianica has the smallest known genome and chromosomes in Orchidaceae, with a genome size of 340.90 Mb (1C) with 35 chromosomes. We predicted a total of 32,412 and 21,724 protein-coding genes for C. singchii and A. fujianica, respectively. The overall BUSCO score was 85.01% for C. singchii and 91.80% in A. fujianica. Based on protein-coding sequences from 55 conserved single-copy families across 21 plant species, we constructed a high-confidence phylogenetic tree and estimated the divergence times. The high-quality genomes of super-giga and tiny orchids offer key insight for future evolutionary researches.

genomics↗

bioRxiv2018

Reduced but not Enhanced Default Mode Network Functional Connectivity in Major Depressive Disorder: Evidence from 25 Cohorts in the REST-meta-MDD Project

Major Depressive Disorder (MDD) is common and disabling, but its neural pathophysiology remains unclear. Functional brain network studies in MDD have largely had limited statistical power and data analysis approaches have varied widely. The REST-meta-MDD Project of resting-state fMRI (R-fMRI) addresses these issues. The 25 research groups in China composing the REST-meta-MDD Project contributed R-fMRI data of 1,300 patients with MDD and 1,128 normal controls (NCs). The data were preprocessed locally with a standardized protocol prior to aggregated group analyses. We focused on functional connectivity (FC) within the default mode network (DMN), frequently reported to show increased FC in MDD. We found decreased instead of increased DMN FC when comparing 848 MDDs with 794 NCs from 17 sites after data exclusion. We found FC reduction only in recurrent MDD, not in first-episode drug-naive MDD. Decreased DMN FC was associated with medication usage but not with MDD duration. DMN FC was also positively related to symptom severity but only in recurrent MDDs. Exploratory analyses also revealed alterations of local intrinsic activity in MDD. We confirmed the key role of DMN in MDD but found reduced rather than increased FC within the DMN. Future studies should test whether decreased DMN FC mediates treatment response. This manuscript announces the publicly available resting-state fMRI indices of the REST-meta-MDD consortium shared via the R-fMRI Maps Project.\n\nSIGNIFICANCE STATEMENTFunctional connectivity within the default mode network in major depressive disorder patients has been frequently reported abnormal but with contradicting directions in previous small sample size studies. By creating the REST-meta-MDD consortium containing neuroimaging data of 1,300 depressed patients and 1,128 normal controls from 25 research groups in China, we found decreased default mode network functional connectivity in depressed patients, driven by patients with recurrent depression, and associated with current medication treatment but not with disease duration. These findings suggest that default mode network functional connectivity remains a prime target for understanding the pathophysiology of depression, with particular relevance to revealing mechanisms of effective treatments.

neuroscience↗