4 research outputs found
Corrigendum: Genome-wide characterization of NAC transcription factors in Camellia sinensis and the involvement of CsNAC28 in drought tolerance
The NAM, ATAF1/2, and CUC2 (NAC) transcription factors, which are members of a plant-specific gene family, play critical roles during the growth and development of plants and in their adaption to environmental stress. Few NAC transcription factors have been functionally characterized in tea plants (Camellia sinensis). Based on the analysis of the gene structure, motif pattern, and evolutionary relationship, we identified 104 NAC genes in C. sinensis. Among them, CsNAC28 is constitutively expressed in all organs, and most significantly, exhibiting remarkable responsiveness to abscisic acid (ABA) treatment and drought stress. ABA is a primary stress-related hormone. Recently, ABA-responsive element binding factor 2 (CsABF2) was identified in the ABA pathway of C. sinensis. However, the involvement of the CsABF2-mediated ABA pathway in regulating CsNACs was not known. Herein, a series of biochemical and genetic approaches supported the fact that CsNAC28 could potentially act as a transcription factor in the downstream of CsABF2. Furthermore, we investigated the function of CsNAC28 in the adapting of a plant to drought stress. The results showed that overexpression of CsNAC28 in Arabidopsis conferred hypersensitivity to ABA treatment and decreased the accumulation of reactive oxygen species (ROS), resulting in improved dehydration tolerance. Under conditions of drought, the expression levels of ABA pathway-related genes and drought stressâinducible genes were greater in CsNAC28 overexpression lines than in the wild type. Our studyâs comprehensive characterization of NAC genes in C. sinensis could serve as a foundation for exploring the molecular mechanism of CsNAC-mediated drought responsiveness.</p
Genome-wide characterization of NAC transcription factors in Camellia sinensis and the involvement of CsNAC28 in drought tolerance
The NAM, ATAF1/2, and CUC2 (NAC) transcription factors, which are members of a plant-specific gene family, play critical roles during the growth and development of plants and in their adaption to environmental stress. Few NAC transcription factors have been functionally characterized in tea plants (Camellia sinensis). Based on the analysis of the gene structure, motif pattern, and evolutionary relationship, we identified 104 NAC genes in C. sinensis. Among them, CsNAC28 is constitutively expressed in all organs, and most significantly, exhibiting remarkable responsiveness to abscisic acid (ABA) treatment and drought stress. ABA is a primary stress-related hormone. Recently, ABA-responsive element binding factor 2 (CsABF2) was identified in the ABA pathway of C. sinensis. However, the involvement of the CsABF2-mediated ABA pathway in regulating CsNACs was not known. Herein, a series of biochemical and genetic approaches supported the fact that CsNAC28 could potentially act as a transcription factor in the downstream of CsABF2. Furthermore, we investigated the function of CsNAC28 in the adapting of a plant to drought stress. The results showed that overexpression of CsNAC28 in Arabidopsis conferred hypersensitivity to ABA treatment and decreased the accumulation of reactive oxygen species (ROS), resulting in improved dehydration tolerance. Under conditions of drought, the expression levels of ABA pathway-related genes and drought stressâinducible genes were greater in CsNAC28 overexpression lines than in the wild type. Our studyâs comprehensive characterization of NAC genes in C. sinensis could serve as a foundation for exploring the molecular mechanism of CsNAC-mediated drought responsiveness
Geometric measure of quantum discord and the geometry of a class of two-qubit states
We investigate the geometric picture of the level surfaces of quantum
entanglement and geometric measure of quantum discord (GMQD) of a class of
X-states, respectively. This pictorial approach provides us a direct
understanding of the structure of entanglement and GMQD. The dynamic evolution
of GMQD under two typical kinds of quantum decoherence channels is also
investigated. It is shown that there exists a class of initial states for which
the GMQD is not destroyed by decoherence in a finite time interval.
Furthermore, we establish a factorization law between the initial and final
GMQD, which allows us to infer the evolution of entanglement under the
influences of the environment.Comment: 10 pages, 4 figures, comments are welcom
Interactive MultiâStage Robotic Positioner for IntraâOperative MRIâGuided Stereotactic Neurosurgery
Abstract Magnetic resonance imaging (MRI) demonstrates clear advantages over other imaging modalities in neurosurgery with its ability to delineate critical neurovascular structures and cancerous tissue in highâresolution 3D anatomical roadmaps. However, its application has been limited to interventions performed based on static pre/postâoperative imaging, where errors accrue from stereotactic frame setup, image registration, and brain shift. To leverage the powerful intraâoperative functions of MRI, e.g., instrument tracking, monitoring of physiological changes and tissue temperature in MRIâguided bilateral stereotactic neurosurgery, a multiâstage robotic positioner is proposed. The system positions cannula/needle instruments using a lightweight (203 g) and compact (Ă97 Ă 81 mm) skullâmounted structure that fits within most standard imaging head coils. With optimized design in soft robotics, the system operates in two stages: i) manual coarse adjustment performed interactively by the surgeon (workspace of ±30°), ii) automatic fine adjustment with precise (<0.2° orientation error), responsive (1.4 Hz bandwidth), and highâresolution (0.058°) soft robotic positioning. Orientation locking provides sufficient transmission stiffness (4.07 N/mm) for instrument advancement. The system's clinical workflow and accuracy is validated with labâbased (<0.8 mm) and MRIâbased testing on skull phantoms (<1.7 mm) and a cadaver subject (<2.2 mm). Customâmade wireless omniâdirectional tracking markers facilitated robot registration under MRI