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Akyol, T. Y.

Publications and source records attributed to Akyol, T. Y..

5 recordsLinked to original sources

A high-quality genome assembly and integrative data portal (Phabase) for the Mesoamerican black bean (Phaseolus vulgaris cv. Negro Jamapa)

Common bean (Phaseolus vulgaris L.) is one of the major legume crops worldwide, constituting a fundamental part of the diet in several countries. In central and south Mexico, the Mesoamerican Negro Jamapa variety is the one of most widely consumed cultivar, and it has notably served as a working model for functional genomics to address the molecular responses to stresses and during the nitrogen-fixing symbiosis with rhizobia. Despite this, the genome sequence of this landrace is not yet available, and the transcriptomic data generated by different research groups on this species are scattered. This prompted us to carry out a de novo sequencing, assembly and gene prediction for Negro Jamapa genome, using Hi-Fi PacBio technology and advanced genomic tools, respectively. Herein, we present a high-quality genome assembly for Negro Jamapa at chromosome level. The assembled genome is 522 Mb length, with an N50 of 45Mb, 89X coverage and BUSCO completeness of 98.4%, parameters that are considerably better than the available Mesoamerican reference genome. In parallel, we built an expression atlas of P. vulgaris from various tissues and growth conditions, by re-mapping publicly available RNA-seq and small RNA-seq data produced in recent years by distinct research groups. This analysis is available for the scientific community in the new user-friendly portal developed in this study, Phabase (https://phabase.ccg.unam.mx/). This portal includes several tools such as BLAST, gene and microRNA expression atlas, JBrowse, download section and integration with other Phaseolus spp. genomes. Significance statementIn this study we report the first genome sequence of Phaseolus vulgaris Negro Jamapa, one of the most widely consumed bean varieties and a key experimental model for multiple research groups. We also developed Phabase (Phabase), an integrated database hosting this genome together with BLAST, JBrowse, and a comprehensive expression atlas. This resource enables functional genomics, comparative analyses, and accelerated breeding of common bean.

plant biology↗

KeySDL: Sparse Dictionary Learning for Keystone Microbe Identification

Identification of microbes with large impacts on their microbial communities, known as keystone microbes, is a topic of long-standing interest in microbiome research. However, many approaches to identify keystone microbes are limited by the inherent nonlinearity and state-dependence of microbial dynamics. Machine learning approaches have been applied to address these shortcomings but often require more data than is available for a given microbial system. We propose a keystone identification approach called KeySDL which reduces the amount of data required by incorporating assumptions about the type of microbial dynamics present in the experimental system. The data are modeled as originating from a Generalized Lotka-Volterra (GLV) model, an architecture commonly used to simulate microbial systems. The parameters of this model are then estimated using Sparse Dictionary Learning (SDL) Compared to existing methods, this approach allows accurate prediction of keystone microbes from small numbers of samples and provides an output interpretable as reconstructed system dynamics. We also propose a self-consistency score to help evaluate whether the assumption of GLV dynamics is reasonable for a given dataset, either through the application of KeySDL or other analysis tools validated using GLV simulation.

bioinformatics↗

Receptor-like kinases FER and SRK mediate Lotus japonicus freezing tolerance and climate adaptation

Many plant species have succeeded in colonizing a wide range of diverse climates through local adaptation, but the underlying molecular genetics remain obscure. We previously found that winter survival was a direct target of selection during colonization of Japan by the perennial legume Lotus japonicus and identified associated candidate genes. Here, we show that two of these, the FERONIA-receptor like kinase (LjFER) and a novel S-receptor-like kinase (LjSRK) are required for non-acclimated freezing tolerance and show haplotype-dependent cold-responsive expression. Our work demonstrates that recruiting a conserved growth regulator, FER, and a novel receptor-like kinase, SRK, into the set of cold-responsive genes has contributed to freezing tolerance and local climate adaptation in L. japonicus, offering new functional genetic insight into perennial herb evolution.

plant biology↗

Genotype by microbiome interactions have large effects on growth in Lotus japonicus

Biological interactions between plants and their root microbiomes are pivotal for plant growth. Even though the plant genotype [G], soil microbiome [C], and growth conditions (environment) [E] are core factors shaping the root microbiome, their relationships remain unclear. We disentangled the effects of G, C, E, and their interactions on the Lotus root microbiome and plant growth using a cross-inoculation approach that reconstructed the interactions between nine Lotus accessions and four soil microbiomes under two different environmental conditions. We found that a large proportion of the root microbiome composition was determined by C and E and that G-related (G, G x C, and G x E) effects were significant but small. In contrast, the interactions between G and C had a more pronounced effect on plant shoot growth than C alone. Our findings indicate that most microbiome variations controlled by C have little effect on the plant phenotype, whereas G x C interactions have more significant effects. Plant genotype-dependent interactions with soil microbes warrant more attention in efforts to optimize crop yield and resilience.

plant biology↗

A chromosome-scale Lotus japonicus Gifu genome assembly indicates that symbiotic islands are not general features of legume genomes

AimLotus japonicus is a herbaceous perennial legume that has been used extensively as a genetically tractable model system for deciphering the molecular genetics of symbiotic nitrogen fixation. Our aim is to improve the L. japonicus reference genome sequence, which has so far been based on Sanger and Illumina sequencing reads from the L. japonicus accession MG-20 and contained a large fraction of unanchored contigs. Methods and ResultsHere, we use long PacBio reads from L. japonicus Gifu combined with Hi-C data and new high-density genetic maps to generate a high-quality chromosome-scale reference genome assembly for L. japonicus. The assembly comprises 554 megabases of which 549 were assigned to six pseudomolecules that appear complete with telomeric repeats at their extremes and large centromeric regions with low gene density. Conclusion and PerspectivesThe new L. japonicus Gifu reference genome and associated expression data represent valuable resources for legume functional and comparative genomics. Here, we provide a first example by showing that the symbiotic islands recently described in Medicago truncatula do not appear to be conserved in L. japonicus.

genomics↗