Gene expression profiling under different photoperiod/temperature conditions in a photoperiod-/thermo-sensitive genic male sterile line of rice (Oryza sativa L.)

A light-controlled DNA nanothermometer for temperature sensing in the cellular membrane microenvironment

Precise sensing of cellular temperature is one significant yet challenge task for studying miscellaneous biological processes. Herein, we report a light-controlled DNA nanothermometer that allow for real-time thermal sensing in extracellular microscope with high spatiotemporal resolution. The light-controlled DNA nanothermometer three key elements: a thermal-sensitive molecular beacon (MB) labelled with fluorophore Cy5 and Cy3 at its 5' and 3' termini, an inhibitor strand containing two photocleavable linkers (pc-linker), and a biotin modified strand, which could modify this three-strand hybridization complex onto the cell surface. Upon exposing to UV light irradiation, the light-controlled DNA nanothermometer could be remotely activated and enable to perform highly sensitive and practical ratiometric temperature sensing. Meanwhile, the light-controlled DNA nanothermometer could conduct temperature sensing in the extracellular microscope and demonstrates desirable sensitivity, excellent reversibility, and quantitative ability for extracellular temperature measurement. Therefore, this light-controlled DNA can serve as a promising tool for elucidating thermal-related cell physiological and pathological processes.

Er-Based Luminescent Nanothermometer to Explore the Real-Time Temperature of Cells under External Stimuli

Temperature as a typical parameter, which influences the status of living creatures, is essential to life activities and indicates the initial cellular activities. In recent years, the rapid development of nanotechnology provides a new tool for studying temperature variation at the micro- or nano-scales. In this study, an important phenomenon is observed at the cell level using luminescent probes to explore intracellular temperature changes, based on Yb-Er doping nanoparticles with special upconversion readout mode and intensity ratio signals (I₅₂₅ and I₅₄₅ ). Further optimization of this four-layer core-shell ratio nanothermometer endows it with remarkable characteristics: super photostability, sensitivity, and protection owing to the shell. Thus this kind of thermal probe has the property of anti-interference to the complex chemical environment, responding exclusively to temperature, when it is used in liquid and cells to reflect external temperature changes at the nanoscale. The intracellular temperature of living RAW and CAOV3 cells are observed to have a resistance mechanism to external stimuli and approach a more favorable temperature, especially for CAOV3 cells with good heat resistance, with the intracellular temperature 4.8 °C higher than incubated medium under 5 °C environment, and 4.4 °C lower than the medium under 60 °C environment.

Fine mapping and candidate gene prediction of the photoperiod and thermo-sensitive genic male sterile gene pms1(t) in rice

Pei'ai64S, an indica sterile variety with photoperiod and thermo-sensitive genic male sterile (PTGMS) genes, has been widely exploited for commercial seed production for "two-line" hybrid rice in China. One PTGMS gene from Pei'ai64S, pms1(t), was mapped by a strategy of bulked-extreme and recessive-class approach with simple sequence repeat (SSR) and insert and deletion (In-Del) markers. Using linkage analysis for the F(2) mapping population consisting of 320 completely male sterile individuals derived from a cross between Pei'ai64S and 93-11 (indica restorer) lines, the pms1(t) gene was delimited to the region between the RM21242 (0.2 cM) and YF11 (0.2 cM) markers on the short arm of chromosome 7. The interval containing the pms1(t) locus, which was co-segregated with RM6776, is a 101.1 kb region based on the Nipponbare rice genome. Fourteen predicted loci were found in this region by the Institute for Genomic Research (TIGR) Genomic Annotation. Based on the function of the locus LOC_Os07g12130 by bioinformatics analysis, it is predicted to encode a protein containing a Myb-like DNA-binding domain, and may process the transcript with thermosensory response. The reverse transcription-polymerase chain reaction (RT-PCR) results revealed that the mRNA levels of LOC_Os07g12130 were altered in different photoperiod and temperature treatments. Thus, the LOC_Os07g12130 locus is the most likely candidate gene for pms1(t). These results may facilitate not only using the molecular marker assisted selection of PTGMS genes, but also cloning of the pms1(t) gene itself.