Biology subjects

Takano, K.

Publications and source records attributed to Takano, K..

4 recordsLinked to original sources

bioRxiv2023

Identification of novel sex determination loci in Japanese weedy melon

Sex expression contributes to fruit quality and yield in the Cucurbitaceae. In melon, orchestrated regulation by sex determination genes explains the mechanism of sex expression, resulting in a great variety of sexual morphologies. In this study, we examined the Japanese weedy melon UT1, which does not follow the reported model of sex expression. We conducted QTL analysis using F2 plants for flower sex on the main stem and the lateral branch and mapped a "femaleness" locus on Chr. 3 (Fem3.1) and a "type of flower femaleness" (female or bisexual) locus on Chr. 8 (tff8.1). Fem3.1 included the known sex determination gene CmACS11. Sequence comparison of CmACS11 between parental lines revealed three nonsynonymous SNPs. A CAPS marker developed from one of the SNPs was closely linked to femaleness in two F2 populations with different genetic backgrounds. The femaleness allele was dominant in F1 lines from crosses between UT1 and diverse cultivars and breeding lines. This study suggests that the identity of tff8.1 is CmCPR5, a recently reported bisexual flower control gene. We found that the Japanese weedy melon UT1 does not follow the conventional sex expression model because of the interaction of the loci Fem3.1 and tff8.1 with the previously reported sex determination genes. The results of this study provide new insights into the molecular mechanisms of sex determination in melons and considerations for the application of femaleness in melon breeding. Key messageJapanese weedy melon exhibits unique sex expression with interactions between previously reported sex determination genes and two novel loci.

plant biology↗

bioRxiv2022

Quantitative analysis of calcium oxalate monohydrate and dihydrate for elucidating the formation mechanism of calcium oxalate kidney stones

We aimed to identify and quantitatively analyze calcium oxalate (CaOx) kidney stones on the order of micrometers, with a focus on the quantitative identification of calcium oxalate monohydrate (COM) and dihydrate (COD). Fourier Transform Infrared (FTIR) spectroscopy, powder X-ray diffraction (PXRD), and microfocus X-ray CT measurements (micro-CT) were performed, and the results were compared. The extended analysis method of the FTIR spectrum, focusing on the 780 cm-1 peak, made it possible to achieve a reliable analysis of the COM/COD ratio. We succeeded in the quantitative analysis of COM/COD in the region of 50 x 50 m by microscopic FTIR for thin sections of kidney stones, and by the micro-CT for bulk samples. The extended analysis method of the FTIR spectrum focusing on the 780 cm-1 peak was introduced to analyze the COM/COD ratio. The analysis results based on PXRD measurement with micro sampling, microscopic FTIR analysis of a thin section, and micro-CT observation of a bulk sample of a kidney stone showed roughly consistent results, indicating that all methods can be used complementarily. This quantitative analysis method evaluates the detailed CaOx composition on the preserved stone surface and provides information on the stone formation processes and interactions with organic molecules.

biophysics↗

bioRxiv2021

Prefrontal-amygdalar oscillations related to social interaction behavior in mice

The medial prefrontal cortex and amygdala are involved in the regulation of social behavior and associated with psychiatric diseases but their detailed neurophysiological mechanisms at a network level remain unclear. We recorded local field potentials (LFPs) from the dorsal medial PFC (dmPFC) and basolateral amygdala (BLA) while mice engaged on social behavior. We found that in wild-type mice, both the dmPFC and BLA increased 4-7 Hz oscillation power and decreased 30-60 Hz power when they needed to attend to another target mouse. In mouse models with reduced social interactions, dmPFC 4-7 Hz power further increased especially when they exhibited social avoidance behavior. In contrast, dmPFC and BLA decreased 4-7 Hz power when wild-type mice socially approached a target mouse. Frequency-specific optogenetic manipulations of replicating social approach-related LFP patterns restored social interaction behavior in socially deficient mice. These results demonstrate a neurophysiological substrate of the prefrontal cortex and amygdala related to social behavior and provide a unified pathophysiological understanding of neuronal population dynamics underlying social behavioral deficits.

neuroscience↗

bioRxiv2021

Dynamic product-precursor relationships underlie cuticular lipid accumulation on maize silks

The hydrophobic cuticle is the first line of defense between aerial portions of a plant and the external environment. On maize silks, the cuticular cutin matrix is infused with cuticular lipids, consisting of a homologous series of very-long-chain fatty acids (VLCFAs), aldehydes, and hydrocarbons that serve as precursors, intermediates, and end-products of the elongation, reduction, and decarbonylation reactions of the hydrocarbon-producing pathway. To deconvolute the potentially confounding impacts of the silk microenvironment and silk development on the hydrocarbon-producing pathway, spatio-temporal cuticular lipid profiling was conducted on the agronomically important inbreds B73 and Mo17, and their reciprocal hybrids. Statistical interrogation via multivariate analyses of the metabolite abundances of the hydrocarbon-producing pathway demonstrate that the cellular VLCFA pool is positively correlated with the cuticular lipid metabolome, and this metabolome is primarily affected by the silk microenvironment and the plant genotype. Moreover, genotype has a major effect on the pathway, with increased cuticular hydrocarbon and concomitant reduction of cuticular VLCFA accumulation on B73 silks, suggesting that conversion of VLCFAs to hydrocarbons is more effective in B73 than Mo17. Statistical modeling of the ratios between cuticular hydrocarbons and cuticular VLCFAs reveals the complexity of the product-precursor ratio relationship, demonstrating a significant role of precursor chain length. Longer-chain VLCFAs are preferentially utilized as precursors for hydrocarbon biosynthesis. Collectively, these findings demonstrate maize silks as an effective and novel system for dissection of the complex dynamics of cuticular lipid accumulation in plants. One-sentence SummaryThe product-precursor ratios in the cuticular hydrocarbon-producing pathway are impacted by fatty acid precursor chain length, plant genotype and the spatio-temporal dynamic gradients of maize silks.

plant biology↗