Biology subjects

Nakayama, N.

Publications and source records attributed to Nakayama, N..

9 recordsLinked to original sources

bioRxiv2026

Cuticulome.org: a centralized database of proteins in arthropod cuticles

Cuticle proteins, especially the cuticular protein (CP) multigene family, are essential for the building, maintenance, and environmental adaptation of the arthropod exoskeleton. The extensive size of CP repertoire, which often represents 1-2% of the protein-coding genes, is a challenge. The discontinuation of previous centralized databases for CPs and the lack of consistent nomenclature in the field have hindered functional analyses and comparative studies. Here, we present Cuticulome.org (accessible at https://www.Cuticulome.org), a curated knowledgebase of proteins that are found in arthropod cuticles. Database entries include protein sequences, tissue and developmental stage specificity, and diverse functional annotations where available, while implementing a standardized nomenclature system to facilitate intra- and cross-species analyses. At Cuticulome.org, users can download complete taxon-specific cuticular proteomes, entire CP families, or build their own custom datasets defined by taxonomic, protein family, functional, or keyword-based criteria. Cuticulome.org also offers two integrated sequence analysis tools: miniBLAST, which allows users to identify putative orthologous CPs, and Cuticular Protein Classifier, which accurately classifies a protein sequence to an established CP family based on custom Hidden Markov Models. Together, these features establish Cuticulome.org as the new centralized resource for systematic analysis of cuticle proteins.

bioinformatics↗

bioRxiv2025

Generation of Region-specific Airway Basal Stem Cells from Human Pluripotent Stem Cells via Regulation of BMP-NOGGIN Axis

Basal cells (BCs) are the primary stem cell population of adult human airways and a key target for hPSC-based models of airway development, disease and regenerative medicine. Recent studies have revealed substantial regional differences between human proximal and distal airway cell types, including BCs. Here, we show that the NOGGIN-BMP signaling axis governs proximal-distal patterning of hPSC-derived lung progenitors leading to the generation of region-specific induced BCs (iBCs). Continuous BMP inhibition through NOGGIN, coupled with tapered WNT activation, generates proximal iBCs that molecularly and functionally resemble human proximal airway BCs and differentiate in vitro and in vivo into the full repertoire of specialized proximal airway cell types, including ionocytes and pulmonary neuroendocrine cells. In sharp contrast, BMP activation with tapered WNT generates distal airway-like cells and distal BCs with limited ionocyte differentiation potential. Progeny of proximal iBCs derived from G551D CFTR mutant hiPSCs also recapitulate a cystic fibrosis-associated ionocyte phenotype.

cell biology↗

bioRxiv2024

Mobius Assembly for Plant Systems uncovers combinatorial interactions among promoters, coding sequences, and terminators in gene regulation

Plants are the primary biological platforms for producing food, energy, and materials in agriculture; however, they remain a minor player in the recent synthetic biology-driven transformation in bioproduction. Molecular tools and technologies for complex, multigene engineering in plants are as yet limited, with the challenge to enhance their stability and predictivity. Here, we present a new standardized and streamlined toolkit for plant synthetic biology, Mobius Assembly for Plant Systems (MAPS). It is based on small plant binary vectors pMAPs, which contain a fusion origin of replication that enhances plasmid yield in both Escherichia coli and Rhizobium radiobacter. MAPS includes a new library of promoters and terminators with different activity levels; part sizes were minimized to improve construct stability and transformation efficiency. These promoters and terminators were characterized using a high-throughput protoplast expression assay. We observed a significant influence of terminators on gene expression, as the strength of a single promoter can change more than seven-folds in combination with different terminators. Changing the coding sequence changed the relative strength of promoter and terminator pairs, thus uncovering combinatorial gene regulation among all parts of a transcriptional unit. We further gained insights into the mechanisms of such interactions by analyzing RNA folding, with which we suggest a design principle for more predictive and context-independent genetic parts in synthetic biology of plant systems and beyond.

synthetic biology↗

bioRxiv2021

Dandelion pappus morphing is actuated by radially patterned material swelling

Plants can generate motion by absorbing and releasing water. Such motion often facilitates reproductive success through the dispersal of seeds and fruits or their self-burial into the soil. Asteraceae plants, such as the dandelion, often have a hairy pappus attached to their fruits to allow them to fly and in many cases, these can open and close depending on moisture levels to modify dispersal. Here we demonstrate the relationship between structure, composition and function of the underlying hygroscopic actuator. By investigating the structure and properties of the actuator cell walls we have identified the mechanism by which the dandelion pappus closes and developed a structural computational model that can capture observed pappus closing. This model was used to explore the contribution of differential material domains in the actuator function and the critical design features. We find that the actuator relies on the radial arrangement of vascular bundles and surrounding tissues including cortex and the floral podium around a central cavity. This allows heterogeneous swelling in a radially symmetric manner to co-ordinate precise movements of the pappus hairs attached at the upper flank. This actuator is a derivative of bilayer structures, but is radial and can synchronise the movement of a planar or lateral attachment. The simple, material-based mechanism presents a promising biomimetic potential in robotics and functional materials.

bioengineering↗

bioRxiv2021

Mobius Assembly for Plant Systems highlights promoter-terminator interaction in gene regulation

Plant synthetic biology is a fast-evolving field that employs engineering principles to empower research and bioproduction in plant systems. Nevertheless, in the whole synthetic biology landscape, plant systems lag compared to microbial and mammalian systems. When it comes to multigene delivery to plants, the predictability of the outcome is decreased since it depends on three different chassis: E. coli, Agrobacterium, and the plant species. Here we aimed to develop standardised and streamlined tools for genetic engineering in plant synthetic biology. We have devised Mobius Assembly for Plant Systems (MAPS), a user-friendly Golden Gate Assembly system for fast and easy generation of complex DNA constructs. MAPS is based on a new group of small plant binary vectors (pMAPs) that contains an origin of replication from a cryptic plasmid of Paracoccus pantotrophus. The functionality of the pMAP vectors was confirmed by transforming the MM1 cell culture, demonstrating for the first time that plant transformation is dependent on the Agrobacterium strains and plasmids; plasmid stability was highly dependent on the plasmid and bacterial strain. We made a library of new short promoters and terminators and characterised them using a high-throughput protoplast expression assay. Our results underscored the strong influence of terminators in gene expression, and they altered the strength of promoters in some combinations and indicated the presence of synergistic interactions between promoters and terminators. Overall this work will further facilitate plant synthetic biology and contribute to improving its predictability, which is challenged by combinatorial interactions among the genetic parts, vectors, and chassis.

synthetic biology↗

bioRxiv2019

A Rab11-GEF Parcas recruits Rab11 onto recycling endosomes for rhodopsin transport in Drosophila photoreceptors

Rab11 and its effectors dRip11 and MyoV are essential for polarized post-Golgi vesicle trafficking to photosensitive membrane rhabdomeres in Drosophila photoreceptors. Here, we found that Parcas (Pcs), recently shown to have guanine-nucleotide-exchange (GEF) activity toward Rab11, co-localizes with Rab11 on the trans-side of Golgi units and post-Golgi vesicles at the base of the rhabdomeres in pupal photoreceptors. Pcs fused with the EM-tag APEX2 localizes on 150-300 nm vesicles at the trans-side of Golgi units, which are presumably fly recycling endosomes (RE). Loss of Pcs impairs Rab11 localization on the trans-side of Golgi units and induces the cytoplasmic accumulation of post-Golgi vesicles bearing rhabdomere proteins, as observed in Rab11-deficiency. In contrast, loss of the specific subunits of TRAPPII, another known Rab11-GEF, does not cause any defects on the eye development nor the transport of rhabdomere proteins, however, simultaneous loss of TRAPPII and Pcs shows severe defects on eye development. These results indicated that in pupal photoreceptors, Pcs is the predominant Rab11-GEF, and TRAPPII performs a function that is redundant but subsidiary to that of Pcs. Summary statementParcas, a Rab11-GEF, recruits Rab11 onto Golgi-associated RE and post-Golgi vesicles in fly photoreceptors. Loss of Parcas results in rhodopsin accumulation within the cytoplasm, similar to that observed under Rab11-deficiency.

cell biology↗

bioRxiv2019

Moisture-dependent morphing tunes the dispersal of dandelion diaspores

Animal migration is highly sensitised to environmental cues, but plant dispersal is considered largely passive. The common dandelion, Taraxacum officinale, bears an intricate haired pappus facilitating flight. The pappus enables the formation of a separated vortex ring during flight; however, the pappus structure is not static but reversibly changes shape by closing in response to moisture. We hypothesised that this leads to changed dispersal properties in response to environmental conditions. Using wind tunnel experiments for flow visualisation, particle image velocimetry, and flight tests we characterised the fluid mechanics effects of the pappus morphing. We also modelled dispersal to understand the impact of pappus morphing on diaspore distribution. Pappus morphing dramatically alters the fluid mechanics of diaspore flight. We found that when the pappus closes in moist conditions, the drag coefficient decreases and thus the falling velocity is greatly increased. Detachment of diaspores from the parent plant also substantially decreases. The change in detachment when the pappus closes increases dispersal distances by reducing diaspore release when wind speeds are low. We propose that moisture-dependent pappus-morphing is a form of informed dispersal allowing rapid responses to changing conditions.

plant biology↗

bioRxiv2017

A biophysical dynamic module for the polarisation of auxin efflux carriers PIN-FORMED (PIN)

Intracellular polarisation of auxin efflux carriers is crucial for understanding how auxin gradients form in plants. The polarisation dynamics of auxin efflux carriers PIN-FORMED (PIN) depends on both biomechanical forces as well as chemical, molecular and genetic factors. Biomechanical forces have shown to affect the localisation of PIN transporters to the plasma membrane. We proposed a biophysical module of PIN polarisation that integrates biomechanical, molecular, and cellular processes as well as their non-linear interactions. The module was implemented as a discrete Boolean model and then approximated to a continuous dynamic system, in order to explore the relative contribution of the factors mediating PIN polarisation at the scale of single cell. Our models recovered qualitative behaviours that have been experimentally observed and enabled us to postulate that, in the context of PIN polarisation, the effects of the mechanical forces can predominate over the activity of molecular factors such as the GTPase ROP6 and the CRIB-motif CRIB-motif RIC1.

plant biology↗

bioRxiv2017

Mobius Assembly: A Versatile Framework For Golden Gate Assembly

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=104 SRC=\"FIGDIR/small/140095_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (16K):\norg.highwire.dtl.DTLVardef@165d4e4org.highwire.dtl.DTLVardef@7bd8f1org.highwire.dtl.DTLVardef@dfbda4org.highwire.dtl.DTLVardef@11b8db9_HPS_FORMAT_FIGEXP M_FIG C_FIG Golden Gate Assembly is a powerful synthetic biology tool, which utilizes Type IIS enzymes for unidirectional assembly of multiple DNA fragments. The simplicity of its DNA assembly and the exchangeability of standard parts greatly facilitate the generation of combinatorial assembly libraries. Currently there are two popular Golden Gate Assembly frameworks that allow multigene augmentation (MoClo and Golden Braid); they render either high cloning capacity or vector toolkit simplicity. We have developed a new Golden Gate Assembly framework called Mobius Assembly, which combines vector toolkit simplicity with high cloning capacity. Mobius Assembly is based on a two-level approach and embraces the standard overhangs defined by MoClo and Golden Braid to confer exchangeability, but with reduced domestication requirement. Furthermore, we have implemented drop-out cassettes encoding chromogenic proteins for visible cloning screening. As proofs of concept, we have functionally assembled up to 16 transcriptional units of various pigmentation genes in both operon and multigene arrangements.

synthetic biology↗