Genome-wide identification and characterization of SRLK gene family reveal their roles in self-incompatibility of Erigeron breviscapus.

Self-incompatibility (SI) is a reproductive protection mechanism that plants acquired during evolution to prevent self-recession. As the female determinant of SI specificity, SRK has been shown to be the only recognized gene on the stigma and plays important roles in SI response. Asteraceae is the largest family of dicotyledonous plants, many of which exhibit self-incompatibility. However, systematic studies on SRK gene family in Asteraceae are still limited due to lack of high-quality genomic data. In this study, we performed the first systematic genome-wide identification of S-locus receptor like kinases (SRLKs) in the self-incompatible Asteraceae species, Erigeron breviscapus, which is also a widely used perennial medicinal plant endemic to China.52 SRLK genes were identified in the E. breviscapus genome. Structural analysis revealed that the EbSRLK proteins in E. breviscapus are conserved. SRLK proteins from E. breviscapus and other SI plants are clustered into 7 clades, and the majority of the EbSRLK proteins are distributed in Clade I. Chromosomal and duplication analyses indicate that 65% of the EbSRLK genes belong to tandem repeats and could be divided into six tandem gene clusters. Gene expression patterns obtained in E. breviscapus multiple-tissue RNA-Seq data revealed differential temporal and spatial features of EbSRLK genes. Among these, two EbSRLK genes having high expression levels in tongue flowers were cloned. Subcellular localization assay demonstrated that both of their fused proteins are localized on the plasma membrane. All these results indicated that EbSRLK genes possibly involved in SI response in E. breviscapus. This comprehensive genome-wide study of the SRLK gene family in E. breviscapus provides valuable information for understanding the mechanism of SSI in Asteraceae.

Voltage compensation based calibration measurement of 3D-acceleration transducer in fall detection system for the elderly.

The fall detection algorithm, which can recognize the fall of human body by collecting the acceleration signals in different directions of the body, is an important part of fall detection system for the elderly. The system, however, may have errors during analyzing the acceleration signal, due to that the coordinate system of the transducer does not coincide with the one of human motion. Furthermore, voltage variation of the battery also influences the accuracy of the acceleration signal. Therefore, in this paper, a fall detection system based on the 3D-acceleration transducer MMA7260 is designed, which can calibrate the acceleration data through compensation of voltage and transformation of coordinates. Experiments illustrated that the proposed method can accurately transform the collected data from the coordinate system of the transducer to that of the human motion, and can recognize various postural changes in the course of the motion of human body.