A key variant in the cis-regulatory element of flowering gene Ghd8 associated with cold tolerance in rice.

Variations in the gene promoter play critical roles in the evolution of important adaptive traits in crops, but direct links of the regulatory mutation to the adaptive change are not well understood. Here, we examine the nucleotide variations in the promoter region of a transcription factor (Ghd8) that control grain number, plant height and heading date in rice. We find that a dominant promoter type of subspecies japonica displayed a high activity for Ghd8 expression in comparison with the one in indica. Transgenic analyses revealed that higher expression levels of Ghd8 delayed heading date and enhanced cold tolerance in rice. Furthermore, a single-nucleotide polymorphism (T1279G) at the position -1279 bp that locates on the potential GA-responsive motif in the Ghd8 promoter affected the expression of this gene. The 1279 T variant has elevated expression of Ghd8, thus conferring increased cold tolerance of rice seedlings. Nucleotide diversity analysis revealed that the approximately 25-kb genomic region surrounding Ghd8 in the subspecies japonica was under significant selection pressure. Our findings demonstrate that the join effects of the regulatory and coding variants largely contribute to the divergence of japonica and indica and increase the adaptability of japonica to the cold environment

2-Ethyl-8-methoxy­methyl-4-oxo-4H-chromen-7-yl (1S,4R)-4,7,7-trimethyl-3-oxo-2-oxabicyclo­[2.2.1]heptane-1-carboxyl­ate

The title compound C23H26O7, was prepared by esterification of 2-ethyl-7-hydr­oxy-8-methoxy­methyl-4H-chromen-4-one with (S)-(−)-camphanic chloride. The two rings of the chromone system are coplanar, making a dihedral angle of 1.99 (19)°, and the camphanoyl unit substituted at 7-O retains the original bicyclo­[2.2.1]heptane conformation of the starting reagent

Multicolor Photodetector of a Single Er3+-Doped CdS Nanoribbon

Er3+-doped CdS nanoribbons (Er-CdS NRs) are synthesized by thermal evaporation and then characterized by field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL), and absorption spectra. The Er-CdS NR photodetector is studied systematically, including spectral response, light intensity response, and photoconductance (G) versus temperature (T). It is found that Er-CdS NR has the ability of detecting multicolor light including blue, red, and near-infrared light with higher responsivity (R-lambda) and external quantum efficiency (eta). The conductance of Er-CdS NR under dark conditions decreases with increasing temperature in the range of 87-237 K, while its conductance increases with increasing temperature in the range of 237-297 K when T is larger than 237 K. These results indicated that ionized impurities and the intrinsic excitation are responsible for the conductance change of Er-CdS NR in the dark. The superior performance of the Er-CdS NR device offers an avenue to develop highly sensitive multicolor photodetector applications.National Natural Science Foundation [11164034]; Yunnan Province Natural Science Foundation [2010DC053]; Key Applied Basic Research Program of Science Technology Commission Foundation of Yunnan Province [2013FA035]; Innovative Talents of Science and Technology Plan Projects of Yunnan Province [2012HA007]SCI(E)[email protected]; [email protected]

Mean Shift-Based Mobile Localization Method in Mixed LOS/NLOS Environments for Wireless Sensor Network

Mobile localization estimation is a significant research topic in the fields of wireless sensor network (WSN), which is of concern greatly in the past decades. Non-line-of-sight (NLOS) propagation seriously decreases the positioning accuracy if it is not considered when the mobile localization algorithm is designed. NLOS propagation has been a serious challenge. This paper presents a novel mobile localization method in order to overcome the effects of NLOS errors by utilizing the mean shift-based Kalman filter. The binary hypothesis is firstly carried out to detect the measurements which contain the NLOS errors. For NLOS propagation condition, mean shift algorithm is utilized to evaluate the means of the NLOS measurements and the data association method is proposed to mitigate the NLOS errors. Simulation results show that the proposed method can provide higher location accuracy in comparison with some traditional methods

Ghd8 controls rice photoperiod sensitivity by forming a complex that interacts with Ghd7

Background: Flowering time is one of the most important agronomic characteristics that ultimately determine yield potential and eco-geographical adaptation in crops. Ghd8 and Ghd7, two major flowering genes, have similar functions and large pleiotropic effects in controlling the heading date, plant height and grain yield of rice. However, these gene interactions at the genetic and molecular levels have not been determined to date. Results: In this study, we investigated the genetic interaction between Ghd8 and Ghd7 by using a set of near-isogenic lines and a panel of natural germplasm accessions in rice. We found that Ghd8 affected multiple agronomic traits in a functional Ghd7-dependent manner. Both functional Ghd8 and Ghd7 are pivotal for rice photoperiod sensitivity controlled by Hd1 and Hd3a. GHD8 could form a heterotrimeric complex with HD1 and OsHAP5b to activate the transcription of Ghd7 by binding directly to the promoter region of Ghd7, which contains the CCAAT-box motif. Conclusions: The results of this study help to elucidate the genetic and molecular bases of Ghd8 and Ghd7 interactions, indicating that Ghd8 acts upstream of Ghd7 to activate its transcription, which inhibits Hd3a expression and thus affects flowering time and rice adaptation

Regulation of CLC-1 chloride channel biosynthesis by FKBP8 and Hsp90β.

Mutations in human CLC-1 chloride channel are associated with the skeletal muscle disorder myotonia congenita. The disease-causing mutant A531V manifests enhanced proteasomal degradation of CLC-1. We recently found that CLC-1 degradation is mediated by cullin 4 ubiquitin ligase complex. It is currently unclear how quality control and protein degradation systems coordinate with each other to process the biosynthesis of CLC-1. Herein we aim to ascertain the molecular nature of the protein quality control system for CLC-1. We identified three CLC-1-interacting proteins that are well-known heat shock protein 90 (Hsp90)-associated co-chaperones: FK506-binding protein 8 (FKBP8), activator of Hsp90 ATPase homolog 1 (Aha1), and Hsp70/Hsp90 organizing protein (HOP). These co-chaperones promote both the protein level and the functional expression of CLC-1 wild-type and A531V mutant. CLC-1 biosynthesis is also facilitated by the molecular chaperones Hsc70 and Hsp90β. The protein stability of CLC-1 is notably increased by FKBP8 and the Hsp90β inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG) that substantially suppresses cullin 4 expression. We further confirmed that cullin 4 may interact with Hsp90β and FKBP8. Our data are consistent with the idea that FKBP8 and Hsp90β play an essential role in the late phase of CLC-1 quality control by dynamically coordinating protein folding and degradation