De novo assembly and inferred functional annotation of the transcriptome of Heterosigma akashiwo

Heterosigma akashiwo is a eukaryotic, cosmopolitan, and unicellular alga (class: Raphidophyceae), and produces fish-killing blooms. There is a substantial scientific and practical interest in its ecophysiological characteristics that determine bloom dynamics and its adaptation to broad climate zones. A well-annotated genomic/genetic sequence information enables researchers to characterize organisms using modern molecular technology. The Chloroplast and the mitochondrial genome sequences and transcriptome sequence assembly (TSA) datasets with limited sizes for H. akashiwo are available in NCBI nucleotide database on December 2021: there is no doubt that more genetic information of the species will greatly enhance the progress of biological characterization of the species. Here, we conducted H. akashiwo RNA sequencing, a de novo transcriptome assembly (NCBI TSA ICRV01) of a large number of high-quality short-read sequences, and the functional annotation of predicted genes. Based on our transcriptome, we confirmed that the organism possesses genes that were predicted to function in phagocytosis, supporting the earlier observations of H. akashiwo bacterivory. Along with its capability for photosynthesis, the mixotrophy of H. akashiwo may partially explain its high adaptability to various environmental conditions. Our study here will provide an important toehold to decipher H. akashiwo ecophysiology at a molecular level.

De novo assembly and inferred functional annotation of the transcriptome of Heterosigma akashiwo

Heterosigma akashiwo is a eukaryotic, cosmopolitan, and unicellular alga (class: Raphidophyceae), and produces fish-killing blooms. There is a substantial scientific and practical interest in its ecophysiological characteristics that determine bloom dynamics and its adaptation to broad climate zones. A well-annotated genomic/genetic sequence information enables researchers to characterize organisms using modern molecular technology. The Chloroplast and the mitochondrial genome sequences and transcriptome sequence assembly (TSA) datasets with limited sizes for H. akashiwo are available in NCBI nucleotide database on December 2021: there is no doubt that more genetic information of the species will greatly enhance the progress of biological characterization of the species. Here, we conducted H. akashiwo RNA sequencing, a de novo transcriptome assembly (NCBI TSA ICRV01) of a large number of high-quality short-read sequences, and the functional annotation of predicted genes. Based on our transcriptome, we confirmed that the organism possesses genes that were predicted to function in phagocytosis, supporting the earlier observations of H. akashiwo bacterivory. Along with its capability for photosynthesis, the mixotrophy of H. akashiwo may partially explain its high adaptability to various environmental conditions. Our study here will provide an important toehold to decipher H. akashiwo ecophysiology at a molecular level.

Natural Coinfection between Novel Species of Baculoviruses in Spodoptera ornithogalli Larvae

Spodoptera ornithogalli (Guenée) (Lepidoptera: Noctuidae) is an important pest in different crops of economic relevance in America. For its control, strategies that include chemicals are usually used; so, the description of entomopathogens would be very useful for the formulation of biopesticides. In this regard, two different baculoviruses affecting S. ornithogalli were isolated in Colombia, with one of them being an NPV and the other a GV. Ultrastructural, molecular, and biological characterization showed that both isolates possess the 38 core genes and are novel species in Baculoviridae, named as Spodoptera ornithogalli nucleopolyhedrovirus (SporNPV) and Spodoptera ornithogalli granulovirus (SporGV). The bioassays carried out in larvae of S. ornithogalli and S. frugiperda showed infectivity in both hosts but being higher in the first. In addition, it was observed that SporGV potentiates the insecticidal action of SporNPV (maximum value in ratio 2.5:97.5). Both viruses are individually infective but coexist in nature, producing mixed infections with a synergistic effect that improves the performance of the NPV and enables the transmission of the GV, which presents a slowly killing phenotype.

Molecular Characterization, Pathogenicity and Biological Characterization of Colletotrichum Species Associated with Anthracnose of Camellia yuhsienensis Hu in China

Camellia yuhsienensis Hu, a species of tea oil tree with resistance to anthracnose, is widely used to breed disease-resistant Camellia varieties. In 2019, anthracnose symptoms were observed on Ca. yuhsienensis for the first time. However, the species and biological characteristics of Colletotrichum spp. isolated from Ca. yuhsienensis (YX-Colletotrichum spp.) have not been elucidated. In this study, five isolates (YX2-5-2, 2YX-3-1, 2YX-5-1, 2YX-8-1-1 and 2YX-8-1-2), which were consistent with the morphological characteristics of Colletotrichum spp., were obtained from Ca. yuhsienensis. A phylogenetic analysis demonstrated that YX2-5-2, 2YX-3-1 and 2YX-8-1-2 belonged to first clade along with Colletotrichum fructicola. 2YX-8-1-1 belonged to the second clade along with Colletotrichum siamense. 2YX-5-1 belonged to the third clade with Colletotrichum camelliae. Pathogenicity tests revealed that the pathogenicity of YX-Colletotrichum spp. was stronger than that of Colletotrichum spp. isolated from Camellia oleifera (GD-Colletotrichum spp.). Biological characteristics illustrated that the mycelial growth of YX-Co. camelliae (2YX-5-1) was slower than that of GD-Co. camelliae when the temperature exceeded 20 °C. In addition, in the presence of ions, the mycelial growth of YX-Co. fructicola (YX2-5-2) and YX-Co. siamense (2YX-8-1-1) was also slower than that of GD-Co. fructicola and GD-Co. siamense. Furthermore, the ability of YX-Colletotrichum spp. to utilize lactose and mannitol was weaker than that of GD-Colletotrichum spp., while the ability to utilize NH4+ was generally stronger than that of GD-Colletotrichum spp. This is the first report of anthracnose of Ca. yuhsienensis induced by Co. fructicola, Co. siamense and Co. camelliae in China. These results will provide theoretical guidance for the study of the pathogenesis and control of anthracnose on Ca. yuhsienensis.

Isolation, Culture and Identification of Bovine Skeletal Stem Cells

The growth plate is essential in long bone formation and contains a wealth of skeletal stem cells (SSCs). Though the origin and the mechanism for SSCs generation remain uncertain, recent studies demonstrate the transition from cartilage to bone that in the lineage for bone development. SSCs possesses the ability to differentiate into bone and cartilage in vitro. In this research, we aimed to isolate and culture the skeletal stem cells from bovine cattle and then studied its biological characterization. The results showed that these bovine SSCs are positive for PDPN+CD73+CD164+CD90+CD44+ cell surface bio-markers, they are capable of self-renewal and differentiation. Our dates proved that SSCs exists in bovine’s long bone.

The Biology of COP Cells: Mesenchymal of Hematopoietic?

Circulating osteogenic precursor (COP) cells constitute a recently discovered population of circulating progenitor cells with the capacity to form not only bone but other mesenchymal tissues. A small but growing body of literature explores these cells, but with a great deal of disagreement and contradiction within it, mainly whether these cells are from mesenchymal or hematopoietic origin. This session will discuss the origins and biological characterization of these cells, including the identification strategies used to isolate these cells from the peripheral blood. It also examines the available knowledge on the in vitro and in vivo behaviour of these cells in plastic adherence, differentiation capacity, proliferation, and cellular homing. We will also review the profound and exciting implications for future use of COP cells in clinical practice, particularly in comparison with other types of stem cells.

Benchmarking a highly selective USP30 inhibitor for enhancement of mitophagy and pexophagy

The deubiquitylase USP30 is an actionable target considered for treatment of conditions associated with defects in the PINK1-PRKN pathway leading to mitophagy. We provide a detailed cell biological characterization of a benzosulphonamide molecule, compound 39, that has previously been reported to inhibit USP30 in an in vitro enzymatic assay. The current compound offers increased selectivity over previously described inhibitors. It enhances mitophagy and generates a signature response for USP30 inhibition after mitochondrial depolarization. This includes enhancement of TOMM20 and SYNJ2BP ubiquitylation and phosphoubiquitin accumulation, alongside increased mitophagy. In dopaminergic neurons, generated from Parkinson disease patients carrying loss of function PRKN mutations, compound 39 could significantly restore mitophagy to a level approaching control values. USP30 is located on both mitochondria and peroxisomes and has also been linked to the PINK1-independent pexophagy pathway. Using a fluorescence reporter of pexophagy expressed in U2OS cells, we observe increased pexophagy upon application of compound 39 that recapitulates the previously described effect for USP30 depletion. This provides the first pharmacological intervention with a synthetic molecule to enhance peroxisome turnover.