Fine Mapping and Candidate Gene Prediction for White Immature Fruit Skin in Cucumber (Cucumis sativus L.).

In this study, a single recessive gene (designated w0) was identified to control the white immature fruit color. Genetic mapping with simple sequence repeats (SSR) markers located the w0 gene in the distal region of cucumber chromosome 3 (Chr.3). Fine mapping was then conducted using the method of draft genome scaffold-assisted chromosome walking with 7304 F2 individuals, which allowed for the assignment of the gene locus to a 100.3 kb genomic DNA region with two flanking markers, Q138 and Q193. Thirteen candidate genes were predicted in the 100.3 kb region. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis showed that the expression of the Csa3G904140 gene, which encodes a two-component response regulator-like protein, was much higher in the immature fruit skin of the green parental line (Q1) than in the white parental line (H4). A coding sequence analysis suggested that a single-base insertion occurred at the ninth exon, resulting in a frameshift mutation in Csa3G904140 of H4, and the mutation was consistent with the phenotype in 17 green/white germplasms. Therefore, Csa3G904140 was taken as the likely candidate gene controlling the immature fruit color of cultivated cucumber. This study will contribute to the cloning of candidate genes and the development of white cucumber cultivars using marker-assisted breeding.

[Monitoring of anesthetic effect based on auditory response time].

OBJECTIVE: To investigate the changes of auditory parameters during anesthesia and establish the assessment indicators for anesthesia monitoring in animal experiments. METHODS: BALB/c mice of 4 to 6 weeks were given a single intraperitoneal dose of urethane, and the auditory evoked potential in the surgically exposed inferior colliculus in response to pure tone stimulation was recorded during urethane metabolism. The latency and amplitude data of the waves were extracted using Matlab software to analyze their variations during urethane metabolism. RESULTS: The latency of the auditory evoked potential showed slight variation and was well correlated to time. The latency decreased progressively during urethane metabolism, fast in the initial 2 h and tending to stabilize afterwards. CONCLUSION: The latency of the auditory evoked potential can be more suitable indicators than the amplitude for anesthetic effect monitoring.

[Response properties of cochlear nucleus neurons: a digital model-based study].

OBJECTIVE: To investigate the mechanisms of different response patterns of the cochlear nucleus neurons based on a digital model. METHODS: Based on the platform of Matlab7.0 and the integrate-and-fire model, we constructed the temporal coding model. RESULTS: The model well simulated the response types of the primary-like, chopper, onset and buildup neurons by changing the settings of some parameters related to the properties of the neurons. CONCLUSIONS: The properties of the neurons dictate the response patterns of the cochlear nucleus neurons. The simulation results are consistent with the literature. Understanding of the response properties of the cochlear nucleus neurons can provide assistance in the study of the auditory system.