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Catalytic hairpin assembly (CHA), as an enzyme‐free isotheral nucleic acid amplification method, can easily cooperate with other amplification procedures to improve the sensitivity and accuracy of detection. Herein, we constructed a cascaded CHA sensing platform for breast cancer biomarker detection. Introducing a short double nucleic acid stand avoids the product of CHA1 to directly trigger the CHA2 reaction, which simplifies the design of the CHA hairpins. Compared with the single CHA2 reaction, the cascaded CHA biosensor activated by microRNA‐155 holds nearly 10 times the amplification efficiency with detection limit down to 47.4 pM and quantifies the target in the range from 50 pM to 200 nM. Besides, the magnetic bead‐confined CHA2 taking 3D DNA walking as the display form contributes to decreasing the environmental interference. As expected, the strategy sensitively distinguishes expression levels of microRNA‐155 in different cell lines and cancer patients, which are consistent with the results of traditional qRT‐PCR method. More importantly, simply adjusting the microRNA recognition sequence of CHA1 can extend the cascaded CHA platform to a wider detection range. Therefore, the robustness and efficiency of the approach enable the potential applications for detection of microRNA and early clinical disease diagnosis. [ABSTRACT FROM AUTHOR]

Desirable biosensing assays need to be sensitive, specific, cost‐effective, instrument‐free, and versatile. Herein we report a new strategy termed CLIPON (CRISPR and Large DNA assembly Induced Pregnancy strips for signal‐ON detection) that can deliver these traits. CLIPON integrates a commercial pregnancy test strip (PTS) with four biological elements: the human chorionic gonadotropin (hCG), CRISPR‐Cas12a, crRNA and cauliflower‐like large‐sized DNA assemblies (CLD). CLIPON uses the Cas12a/crRNA complex both to recognize a target of interest and to release CLD‐bound hCG so that target presence can translate into a colorimetric signal on the PTS. We demonstrate the versatility of CLIPON through sensitive and specific detection of HPV genomic DNA, SARS‐CoV‐2 genomic RNA and adenosine. We also engineer a cell phone app and a hand‐held microchip to achieve signal quantification. CLIPON represents an attractive option for biosensing and point‐of‐care diagnostics. [ABSTRACT FROM AUTHOR]

As two of the most important environmental factors, light and temperature regulate almost all aspects of plant growth and development. Under natural conditions, light is accompanied by warm temperatures and darkness by cooler temperatures, suggesting that light and temperature are tightly associated signals for plants. Indeed, accumulating evidence shows that plants have evolved a wide range of mechanisms to simultaneously perceive and respond to dynamic changes in light and temperature. Notably, the photoreceptor phytochrome B (phyB) was recently shown to function as a thermosensor, thus reinforcing the notion that light and temperature signaling pathways are tightly associated in plants. In this review, we summarize and discuss the current understanding of the molecular mechanisms integrating light and temperature signaling pathways in plants, with the emphasis on recent progress in temperature sensing, light control of plant freezing tolerance, and thermomorphogenesis. We also discuss the questions that are crucial for a further understanding of the interactions between light and temperature signaling pathways in plants. [ABSTRACT FROM AUTHOR]

There is a constant drive for affordable point‐of‐care testing (POCT) technologies for the detection of infectious human diseases. Herein, we report a simple platform for DNA detection that takes advantage of four techniques: commercially available pregnancy test strips (PTS), amplicon generation via loop‐mediated isothermal amplification (LAMP), toehold‐mediated strand displacement, and noncovalent immobilization of DNA on paper surface with DNA nanoflowers. This simple, separation‐free platform is highly specific, as demonstrated with the detection of rtL180M, a single‐nucleotide polymorphism observed in hepatitis B virus (HBV) associated with antiviral drug resistance. It is very sensitive, capable of detecting the targeted mutation at 2 copies μL−1. It is able to correctly identify the unmutated and rtL180M genome types of HBV in clinical samples. Given its wide adaptability, we expect this platform can be easily modified for the detection of genetic variations associated with various pathogens and human diseases. [ABSTRACT FROM AUTHOR]

Light and temperature are two core environmental factors that coordinately regulate plant growth and survival throughout their entire life cycle. However, the mechanisms integrating light and temperature signaling pathways in plants remain poorly understood. Here, we report that CBF1, an AP2/ERF‐family transcription factor essential for plant cold acclimation, promotes hypocotyl growth under ambient temperatures in Arabidopsis. We show that CBF1 increases the protein abundance of PIF4 and PIF5, two phytochrome‐interacting bHLH‐family transcription factors that play pivotal roles in modulating plant growth and development, by directly binding to their promoters to induce their gene expression, and by inhibiting their interaction with phyB in the light. Moreover, our data demonstrate that CBF1 promotes PIF4/PIF5 protein accumulation and hypocotyl growth at both 22°C and 17°C, but not at 4°C, with a more prominent role at 17°C than at 22°C. Together, our study reveals that CBF1 integrates light and temperature control of hypocotyl growth by promoting PIF4 and PIF5 protein abundance in the light, thus providing insights into the integration mechanisms of light and temperature signaling pathways in plants. Synopsis: CBF1, a key regulator of plant cold acclimation, enhances Arabidopsis hypocotyl growth under ambient temperatures by promoting light‐dependent accumulation of phytochrome‐interacting transcription factors PIF4 and PIF5. CBF1 thus integrates light and temperature control of hypocotyl growth in Arabidopsis. CBF1 physically interacts with phytochromes phyA and phyB.phyA and phyB increase CBF1 protein levels in the light.CBF1 increases PIF4/PIF5 protein levels through transcriptional and post‐translational regulatory mechanisms.CBF1 regulation of PIF4/PIF5 protein abundance and hypocotyl growth is temperature‐dependent. [ABSTRACT FROM AUTHOR]

Summary: Group A protein phosphatase 2Cs (PP2Cs) are abscisic acid (ABA) co‐receptors that negatively regulate the ABA signaling pathway by inhibiting the downstream SnRK2 protein kinases. It has long been observed that exogenous ABA treatments dramatically induce the expression of group A PP2C genes, but the underlying molecular mechanisms and the biological significance remain largely unknown.Here, by using GUS reporter transgenic lines in which various lengths of ABI1 and ABI2 promoters were used to drive GUS gene expression, we defined the promoter fragments that confer ABA inducibility to ABI1 and ABI2. We further showed that ABRE‐binding factors (ABFs), the bZIP family transcription factors, directly bind to the promoters of group A PP2C genes, and mediate rapid induction of their expression on exogenous ABA treatments.Moreover, our data indicated that ABA dramatically induces the expression of ABF genes and the accumulation of endogenous ABF proteins, and that ABFs themselves are involved in this induction, thus providing another layer of ABA regulation towards ABF proteins in addition to the well‐characterized ABA‐induced phosphorylation by SnRK2 protein kinases.Together, our data demonstrate that ABFs mediate rapid ABA induction of group A PP2C genes, thus playing a role in the negative feedback regulation of ABA signaling. [ABSTRACT FROM AUTHOR]