Overexpression of rice F-box phloem protein gene OsPP12-A13 confers salinity tolerance in Arabidopsis

Salinity is a serious challenge for agriculture production by limiting the arable land.Rice is a major staple food crop but very sensitive to salt stress.In this study,we used Arabidopsis for the functional characterization of a rice F-box gene LOC_Os04g48270(OsPP12-A13)under salinity stress.OsPP12-A13 is a nuclear-localized protein that is strongly upregulated under salinity stress in rice and showed the highest expression in the stem,followed by roots and leaves.Two types of transgenic lines for OsPP12-A13 were generated,including constitutive tissue over-expression using the CaMV35S promoter and phloem specific over-expression using the pSUC2 promoter.Both types of transgenic plants showed salinity tolerance at the seedling stage through higher germination percentage and longer root length,as compared to control plants under salt stress in MS medium.Both the transgenic plants also exhibited salt tolerance at the reproductive stage through higher survival rate,plant dry biomass,and seed yield per plant as compared to control plants.Determination of Na+concentration in leaves,stem and roots of salt-stressed transgenic plants showed that Na^(+) concentration was less in leaf and stem as compared to roots.The opposite was observed in wild type stressed plants,suggesting that OsPP12-A13 may be involved in Na+transport from root to leaf.Transgenic plants also displayed less ROS levels and higher activities of peroxidase and glutathione S-transferase along with upregulation of their corresponding genes as compared to control plants which further indicated a role of OsPP12-A13 in maintaining ROS homeostasis under salt stress.Further,the non-significant difference between the transgenic lines obtained from the two vectors highlighted that OsPP12-A13 principally works in the phloem.Taken together,this study showed that OsPP12-A13 improves salt tolerance in rice,possibly by affecting Na^(+) transport and ROS homeostasis.

DOA Estimation Based on Subspace Compensation for Unfolded Coprime Array

Direction of arrival(DOA)estimation for unfolded coprime array(UFCA)is discussed,and a method based on subspace compensation is proposed.Conventional DOA estimation meth-ods partition the UFCA into two subarrays for separate estimations,which are then combined for unique DOA determination.However,the DOA estimation performance loss is caused as only the partial array aperture is exploited.We use the estimations from one subarray as initial estimations,and then enhance the estimation results via a compensation based on the whole array,which is im-plemented via a simple least squares(LS)operation constructed from the initial estimation and first-order Taylor expansion.Compared to conventional methods,the DOA estimation performance is improved while the computational complexity is in the same level.Multiple simulations are con-ducted to verify the efficiency of the proposed approach.

Pathologically expanded peripheral CD4^(+)PD-1^(+)Foxp3^(−) T-cell subset promotes B-cell hyperactivity in patients with rheumatoid arthritis

Background:Rheumatoid arthritis (RA) is an autoimmune disease characterized by destructive polyarthritis, and abnormal T-B-cell interactions may contribute to its pathogenesis. This study aimed to investigate the characteristics and roles of CD4^(+) programmed death 1 (PD-1)^(+)Foxp3^(−) T cells in relation to the B-cell response in patients with RA. Methods:This study included 155 patients with RA and 36 age- and sex-matched healthy controls (HCs) from the Second Hospital of Dalian Medical University in China. Flow cytometry was used to assess the proportion and properties of peripheral CD4^PD-1^(−)Foxp3^(+) T cells, including their proliferation, activation, cytokine production, and capacity to induce B-cell differentiation. Results:The proportion of CD4^(+)PD-1^(+)Foxp3^(−)T cells was increased in patients with RA compared with HCs ([10.78 ± 0.60]% vs. [5.67 ± 0.40]%, p < 0.001), and this was positively associated with the B-cell response. Compared with CD4^PD-1 ^(+)Foxp3 ^(+) T cells, CD4^(+)PD-1^(+)Foxp3^(−)T cells from patients with RA exhibited increased expression of Ki67 ([6.52 ± 0.41]% vs. [3.87 ± 0.42]%, p < 0.01) and activation markers, produced higher levels of cytokines, and showed enhanced B-cell differentiation. Furthermore, anti-interleukin-6R antagonists decreased the proportion, activation, and cytokine production of CD4^(+)PD-1^(+)Foxp3^(−)T cells in vitro. The frequency of type 2 CD4^(+)PD-1^(+)Foxp3^(−)T cells was significantly higher in patients with RA than that in HCs ([37.27 ± 1.43]% vs. [29.05 ± 1.30]%, p < 0.05). Conclusions:Peripherally expanded CD4^(+)PD-1^(+)Foxp3^(−)T cells in patients with RA, which induced B-cell hyperactivity, may be inclined toward type 2 helper T cells. Our findings revealed a novel T-cell subset that contributes to B-cell hyperactivity in the pathogenesis of RA.

Direct and single-step sensing of primary ovarian cancers related glycosidases

High sensitive,accurate detection for tumor-associated overexpressed enzyme activity is highly significant for further understanding enzyme function,discovering potential drugs,and early diagnosis and prevention of diseases.In this work,we developed a facile,direct and single-step detection platform for primary ovarian cancers related glycosidase activity based on the inner filter effect(IFE)between glycosidase catalytic product and black phosphorus quantum dots(BPQDs).Highly fluorescent BPQDs were successfully synthesized from bulk black phosphorus by a simple liquid exfoliation method.Under the catalysis ofβ-galactosidase,p-nitrophenyl-β-D-galactopyranoside(PNPG)was transformed into pnitrophenol(PNP)andβ-D-galactopyranoside.Meanwhile,the absorption of catalytic product PNP greatly overlapped with the excitation and emission spectra of fluorescent BPQDs,leading to the fluorescence quenching of BPQDs with a high quenching efficiency.The proposed sensing strategy provided a low detection limit of 0.76 U/L,which was 1-2 orders of magnitude lower than most unmodified sensing platforms.D-Galactal was selected as the inhibitor forβ-galactosidase to further assess the feasibility of screening potential inhibitors.The fluorescence recovery of BPQDs suggests that the unmodified sensing platform is feasible to discover potential drugs ofβ-galactosidase.Our work paves a general way in the detection of glycosidase activity with fluorescent BPQDs,which can be promising for glycosidase-related disease diagnosis and pathophysiology elucidation.

Photoresponsive Biomimetic Protocells for Near-Infrared-Light- Regulated Phototheranostics

Nature has created complex living systems with outstanding structure and remarkable function.Constructing biomimetic systems that rival living organisms has attracted considerable research inter-est in research fields of self-assembly and bionic sci-ence.