An E3 ubiquitin ligase CSIT2 controls critical sterility-inducing temperature of thermo-sensitive genic male sterile rice.

Thermo-sensitive genic male sterile (TGMS) lines are the core of two-line hybrid rice (Oryza sativa). However, elevated or unstable critical sterility-inducing temperatures (CSITs) of TGMS lines are bottlenecks that restrict the development of two-line hybrid rice. However, the genes and molecular mechanisms controlling CSIT remain unknown. Here, we report the CRITICAL STERILITY-INDUCING TEMPERATURE 2 (CSIT2) that encodes a really interesting new gene (RING) type E3 ligase, controlling the CSIT of thermo-sensitive male sterility 5 (tms5)-based TGMS lines through ribosome-associated protein quality control (RQC). CSIT2 binds to the large and small ribosomal subunits and ubiquitinates 80S ribosomes for dissociation, and may also ubiquitinate misfolded proteins for degradation. Mutation of CSIT2 inhibits the possible damage to ubiquitin system and protein translation, which allows more proteins such as catalases to accumulate for anther development and inhibits abnormal accumulation of reactive oxygen species (ROS) and premature programmed cell death (PCD) in anthers, partly rescuing male sterility and raised the CSIT of tms5-based TGMS lines. These findings reveal a mechanism controlling CSIT and provide a strategy for solving the elevated or unstable CSITs of tms5-based TGMS lines in two-line hybrid rice.

The E3 ubiquitin ligase CSIT1 regulates critical sterility-inducing temperature by ribosome-associated quality control to safeguard two-line hybrid breeding in rice.

Two-line hybrid breeding can fully utilize heterosis in crops. In thermo-sensitive genic male sterile (TGMS) lines, low critical sterility-inducing temperature (CSIT) is vital to safeguard the production of two-line hybrid seeds in rice (Oryza sativa), but the molecular mechanism determining CSIT is unclear. Here, we report the cloning of CSIT1, which encodes an E3 ubiquitin ligase, and show that CSIT1 modulates the CSIT of thermo-sensitive genic male sterility 5 (tms5)-based TGMS lines through ribosome-associated quality control (RQC). Biochemical assays demonstrated that CSIT1 binds to the 80S ribosomes and ubiquitinates abnormal nascent polypeptides for degradation in the RQC process. Loss of CSIT1 function inhibits the possible damage of tms5 to the ubiquitination system and protein translation, resulting in enhanced accumulation of anther-related proteins such as catalase to suppress abnormal accumulation of reactive oxygen species and premature programmed cell death in the tapetum, thereby leading to a much higher CSIT in the tms5-based TGMS lines. Taken together, our findings reveal a regulatory mechanism of CSIT, providing new insights into RQC and potential targets for future two-line hybrid breeding.

BOTRYOID POLLEN 1 regulates ROS-triggered PCD and pollen wall development by controlling UDP-sugar homeostasis in rice.

Uridine diphosphate (UDP)-sugars are important metabolites involved in the biosynthesis of polysaccharides and may be important signaling molecules. UDP-glucose 4-epimerase (UGE) catalyzes the interconversion between UDP-Glc and UDP-Gal, whose biological function in rice (Oryza sativa) fertility is poorly understood. Here, we identify and characterize the botryoid pollen 1 (bp1) mutant and show that BP1 encodes a UGE that regulates UDP-sugar homeostasis, thereby controlling the development of rice anthers. The loss of BP1 function led to massive accumulation of UDP-Glc and imbalance of other UDP-sugars. We determined that the higher levels of UDP-Glc and its derivatives in bp1 may induce the expression of NADPH oxidase genes, resulting in a premature accumulation of reactive oxygen species (ROS), thereby advancing programmed cell death (PCD) of anther walls but delaying the end of tapetal degradation. The accumulation of UDP-Glc as metabolites resulted in an abnormal degradation of callose, producing an adhesive microspore. Furthermore, the UDP-sugar metabolism pathway is not only involved in the formation of intine but also in the formation of the initial framework for extine. Our results reveal how UDP-sugars regulate anther development and provide new clues for cellular ROS accumulation and PCD triggered by UDP-Glc as a signaling molecule.

Effects of Ranibizumab combined with laser photocoagulation on macular volume and best corrected visual acuity in patients with macular edema secondary to ischemic retinal vein occlusion.

Objective: To investigate the effects of ranibizumab combined with laser photocoagulation on macular volume and best corrected visual acuity (BCVA) in patients with macular edema secondary to ischemic retinal vein occlusion. Methods: The clinical data of 90 patients (90 eyes) with macular edema secondary to ischemic retinal vein occlusion treated in our hospital from June 2018 to December 2021 were retrospectively analyzed. Patients were divided into Groups-A, B, and C according to the type of treatment they received. The Group-A was treated with laser photocoagulation, the Group-B was intravitreally injected with ranibizumab, and the Group-C underwent ranibizumab combined with laser photocoagulation. The efficacy, intraocular pressure, BCVA, central macular thickness (CMT) and adverse reactions were compared among the three groups. Results: The total efficacy of the Group-C was higher than that of the Group-A and B, with statistically significant differences (P< 0.05). Three months after treatment, BCVA was higher while CMT was reduced in the Group-C than those in the Group-A and B (P < 0.05). Six months after treatment, BCVA was higher while intraocular pressure was lower and CMT was thinner in the group C compared with the Group-A and B (P< 0.05). Conclusions: Ranibizumab combined with laser photocoagulation in the treatment of macular edema secondary to ischemic retinal vein occlusion presents significant efficacy, and can effectively reduce macular volume, improve visual acuity and promote the recovery of retinal function.

Current Status and Associated Factors of Health Information Literacy Among the Community Elderly in Central China in the COVID-19 Pandemic: A Cross-Sectional Study.

Purpose: COVID-19 posed a threat to the public's physical and mental health, and under outbreak control, the opportunities to go outside of the elderly have been reduced and making it more difficult to access health information and detrimental to their health management. This study aims to assess the current status of health information literacy (HIL) among older adults in the community in the context of COVID-19 and to identify its associated factors. Methods: A cross-sectional survey was conducted from April to July, 2021, for which 617 community elderly members were recruited in Chenzhou, China. Data were collected through a general information questionnaire, The Chinese residents' HIL self-rated scale and a reliability evaluation form. Results: The average score of HIL was 75.87 ± 9.85, and after processed by the 100-point system, we found 84.12% (519/617) of the participants scored less than 60 points, which indicates that the overall level of HIL among the community elderly is low. Multiple linear regression showed that age, gender, education, annual family Income, living arrangement, and chronic disease status (ß = -0.341, -0.296, 0.384, 0.327, 0.296, 0.356, respectively; all P < 0.001) were significantly associated with the level of HIL found among the community elderly, out of which education was the most important associated factor. Conclusion: The overall HIL level among the community elderly was low in Central China during the COVID-19 pandemic. Our results further prove the need for tailor-made health education programs for this group, with particular attention paid to the low-educated and low-income among them. Those measures must highlight on three aspects of health information search, evaluation, and application skills to offer useful experiences that improve the HIL level of the elderly and strengthen their ability to cope with emerging public health events.

Comparative physiological and transcriptomic analyses illuminate common mechanisms by which silicon alleviates cadmium and arsenic toxicity in rice seedlings.

The inessential heavy metal/loids cadmium (Cd) and arsenic (As), which often co-occur in polluted paddy soils, are toxic to rice. Silicon (Si) treatment is known to reduce Cd and As toxicity in rice plants. To better understand the shared mechanisms by which Si alleviates Cd and As stress, rice seedlings were hydroponically exposed to Cd or As, then treated with Si. The addition of Si significantly ameliorated the inhibitory effects of Cd and As on rice seedling growth. Si supplementation decreased Cd and As translocation from roots to shoots, and significantly reduced Cd- and As-induced reactive oxygen species generation in rice seedlings. Transcriptomics analyses were conducted to elucidate molecular mechanisms underlying the Si-mediated response to Cd or As stress in rice. The expression patterns of the differentially expressed genes in Cd- or As-stressed rice roots with and without Si application were compared. The transcriptomes of the Cd- and As-stressed rice roots were similarly and profoundly reshaped by Si application, suggesting that Si may play a fundamental, active role in plant defense against heavy metal/loid stresses by modulating whole genome expression. We also identified two novel genes, Os01g0524500 and Os06g0514800, encoding a myeloblastosis (MYB) transcription factor and a thionin, respectively, which may be candidate targets for Si to alleviate Cd and As stress in rice, as well as for the generation of Cd- and/or As-resistant plants. This study provides valuable resources for further clarification of the shared molecular mechanisms underlying the Si-mediated alleviation of Cd and As toxicity in rice.

OsCER1 regulates humidity-sensitive genic male sterility through very-long-chain (VLC) alkane metabolism of tryphine in rice.

Humidity-sensitive genic male sterility (HGMS) is a novel type of environment-sensitive male sterility (EGMS) which plants are male sterile at low humidity and male fertile at high humidity. Previous studies have revealed that OsCER1 contributes to very-long-chain (VLC) alkanes biosynthesis in rice (Oryza sativa L.). Here, applying the CRISPR/Cas9 technique, we obtained two independent OsCER1 knockout lines (OsCER1Cas). Both OsCER1Cas lines exhibited HGMS. Mutant pollen showed defects in adhesion and germination on stigmas at low humidity, whereas high humidity enhanced the pollen germination rate. Transmission electron microscopy (TEM) observations of mutant pollen revealed abnormal tryphine structure, potentially representing the basis of HGMS. Furthermore, co-pollination with mixed OsCER1Cas mutant and maize (Zea mays L.) pollen could rescue the fertility of the mutant, thereby establishing the key role of tryphine in germination on stigmas. OsCER1 knockout might affect VLC alkane metabolism and therefore alter the lipid composition of tryphine. It could lead to the defects in pollen grain adhesion, hydration and germination, resulting in HGMS. This work identified the mechanism of HGMS induced by VLC alkanes in rice and the generality of tryphine in different species of Gramineae.

Natural polymorphisms in a pair of NSP2 homoeologs can cause loss of nodulation in peanut.

Microbial symbiosis in legumes is achieved through nitrogen-fixing root nodules, and these are important for sustainable agriculture. The molecular mechanisms underlying development of root nodules in polyploid legume crops are largely understudied. Through map-based cloning and QTL-seq approaches, we identified a pair of homoeologous GRAS transcription factor genes, Nodulation Signaling Pathway 2 (AhNSP2-B07 or Nb) and AhNSP2-A08 (Na), controlling nodulation in cultivated peanut (Arachis hypogaea L.), an allotetraploid legume crop, which exhibited non-Mendelian and Mendelian inheritance, respectively. The segregation of nodulation in the progeny of Nananbnb genotypes followed a 3:1 Mendelian ratio, in contrast to the 5:3~1:1 non-Mendelian ratio for nanaNbnb genotypes. Additionally, a much higher frequency of the nb allele (13%) than the na allele (4%) exists in the peanut germplasm collection, suggesting that Nb is less essential than Na in nodule organogenesis. Our findings reveal the genetic basis of naturally occurred non-nodulating peanut plants, which can be potentially used for nitrogen fixation improvement in peanut. Furthermore, the results have implications for and provide insights into the evolution of homoeologous genes in allopolyploid species.

HMS1 interacts with HMS1I to regulate very-long-chain fatty acid biosynthesis and the humidity-sensitive genic male sterility in rice (Oryza sativa).

Environment-sensitive genic male sterility (EGMS) lines are used widely in two-line hybrid breeding in rice (Oryza sativa). At present, photoperiod-sensitive genic male sterility (PGMS) lines and thermo-sensitive genic male sterility (TGMS) lines are predominantly used in two-line hybrid rice, with humidity-sensitive genic male sterility (HGMS) lines rarely being reported. Here, it is shown that HUMIDITY-SENSITIVE GENIC MALE STERILITY 1 (HMS1), encoding a ß-ketoacyl-CoA synthase, plays key roles in the biosynthesis of very-long-chain fatty acids (VLCFAs) and HGMS in rice. The hms1 mutant displayed decreased seed setting under low humidity, but normal seed setting under high humidity. HMS1 catalyzed the biosynthesis of the C26 and C28 VLCFAs, contributing to the formation of bacula and tryphine in the pollen wall, which protect the pollen from dehydration. Under low-humidity conditions, hms1 pollen showed poor adhesion and reduced germination on the stigmas, which could be rescued by increasing humidity. HMS1-INTERACTING PROTEIN (HMS1I) interacted with HMS1 to coregulate HGMS. Furthermore, both japonica and indica rice varieties with defective HMS1 exhibited HGMS, suggesting that hms1 potentially could be used in hybrid breeding. The results herein reveal the novel mechanism of VLCFA-mediated pollen wall formation, which protects pollen from low-humidity stress in rice, and has a potential use in hybrid crop breeding.

A transcriptomic (RNA-seq) analysis of genes responsive to both cadmium and arsenic stress in rice root.

Cadmium (Cd) and arsenic (As) are nonessential and toxic elements in rice that often occur together in contaminated paddy field soils. To understand whether rice has a common molecular response mechanism against Cd and As toxicity, 30-day seedlings (Oryza sativa L. indica) were exposed separately to Cd and As3+ in hydroponic cultures for up to 7 days. Root transcriptomic analysis of plants exposed to Cd and As for 3 days revealed that a total of 2224 genes in rice roots responded to Cd stress, while 1503 genes responded to As stress. Of these, 841 genes responded to both stressors. The genes in common to Cd and As stress were associated with redox control, stress response, transcriptional regulation, transmembrane transport, signal transduction, as well as biosynthesis and metabolism of macromolecules and sulfur compounds. In plants exposed to Cd and As separately or in combination for 3 and 7 days, qRT-PCR verification revealed that the glutathione metabolism associated gene Os09g0367700 was significantly up-regulated with respect to unexposed controls and had a positive synergistic effect under combined Cd and As stress. In addition, the redox control related genes Os06g0216000, Os07g0638300 and Os01g0294500, the glutathione metabolism related gene Os01g0530900, the cell wall biogenesis related genes Os05g0247800, Os11g0592000 and Os03g0416200, the expression regulation related genes Os07g0597200 and Os02g0168200, and the transmembrane transport related genes Os04g0524500, also varied significantly with respect to an unexposed control and displayed synergistic effects after 7 days of simultaneous exposure to Cd and As. Our identification of a novel set of genes in rice which responded to both Cd and As3+ stress may be of value in mitigating the toxicity of co-contaminated soils. These results also provide a deeper understanding of the molecular mechanisms involved in response to multi-metal/loids stress, and may be used in the genetic improvement of rice varieties.

Comparative genomic hybridization and transcriptome sequencing reveal that two genes, OsI_14279 (LOC_Os03g62620) and OsI_10794 (LOC_Os03g14950) regulate the mutation in the γ-rl rice mutant.

We previously established the genetic locus of the rolled-leaf mutant, γ-rl, to chromosome 3. In this study, we performed a comparative genomic hybridization (CGH) analysis to identify the genes responsible for the γ-rl mutant phenotype. This was combined with RNA transcriptome sequencing (RNA-seq) to analyze differences in the mRNA expression in seeds 12 h after germination. Using the reference genome of the "indica type" rice from GenBank, we created a chip with 386,000 high density DNA probes designed to target chromosome 3. The genomic DNA from γ-rl and Qinghuazhan (the wild-type) was used for hybridization against the chip to compare signal differences. We uncovered 49 regions with significant differences in hybridization signals including deletions and insertions. RNA-seq analysis between γ-rl and QHZ identified 1060 differentially expressed genes, which potentially regulate numerous biological activities. Moreover, we identified 72 annotated genes in the 49 regions discovered in CGH. Among these, 44 genes showed differential expression in RNA-seq. qRT-PCR validation of the candidate genes confirmed that seven of the 44 genes showed a significant change in their expression levels. Among these, four genes [OsI_10125 (LOC_Os03g06654), OsI_14045 (LOC_Os03g62490), OsI_14279 (LOC_Os03g62620) and OsI_14326 (LOC_Os03g63250)] were down regulated and three genes [(OsI_10794 (LOC_Os03g14950), OsI_11412 (LOC_Os03g21250) and OsI_14152 (LOC_Os03g61360)] were up regulated with a fold change ≥2.0 and a P value ≤ 0.01. Finally, we constructed transgenic plants to study the in vivo functions of these genes. RNAi knock down of LOC_Os03g62620 resulted in rolled-leaf, lower seed-setting and decreased seed growth phenotypes. Transgenic plants with LOC_Os03g14950 over-expression showed dwarf plants with a shortened leaf phenotype. Our results, LOC_Os03g62620 and LOC_Os03g14950 as the essential genes responsible for creating the γ-rl mutant phenotypes suggested that these genes may play crucial roles in regulating rice leaf development and seed growth.

Clinical characteristics of a KIF21A mutation in a Chinese family with congenital fibrosis of the extraocular muscles type 1.

The aim of the study is to characterize the clinical ocular phenotype with congenital fibrosis of the extraocular muscles type 1 (CFEOM1) and to confirm whether the kinesin family member 21A (KIF21A) mutation was the pathogenic gene in this Chinese family.Three affected individuals and 2 asymptomatic kinsfolk from a Chinese family underwent comprehensive ophthalmic examinations, orbital computerized tomography (CT), and postoperative histological examinations were performed in the proband. All the recruited members were screened for 3 exons (8, 20, and 21) of KIF21A mutations using the polymerase chain reaction (PCR) amplification and direct sequencing of corresponding PCR products.All patients shared the clinical characteristics including bilateral ophthalmoplegia, blepharoptosis, hypertropic, and exotropic position with inability to raise either eye above the midline and a chin-up head position. Direct DNA sequence analysis from the affected members revealed a missense mutation in KIF21A (c.2860C>T, p.R954W). The unaffected members did not harbor the p.R954W mutation. The candidate mutation was not present in multiple web-accessible and in-house exome databases.The p.Arg954Trp mutation of KIF21A was the causative mutation in this Chinese pedigree with CFEOM1.

[Observation on clinical therapeutic effect of acupuncture on upper limb spasticity in the patient of poststroke].

OBJECTIVE: To observe therapeutic effect of acupuncture at acupoints selected according to rehabilitation medical theory on upper limb spasticity in the patient of poststroke. METHODS: Sixty cases were randomly divided into an acupuncture group and an electro-stimulation group, 30 cases in each group. The acupuncture group were treated by acupuncture at the contralateral scalp motor region of the affected limb, Jiquan (HT 1), Chize (LU 5), Daling (PC 7) on the flexor side and Jianyu (LI 15), Tianjing (TE 10), Yangchi (TE 4) on the extensor muscle side of the affected limb; the electro-stimulation group were treated by electric stimulation. The two groups also were treated with necessary medical treatment and anti-spasm rehabilitation motor training. The course was 3 weeks. Modified Ashworth Scale for muscle spasm (MAS), modified Fugl-Meyer Assessment (FMA) for upper limb motor function, and Modified Barthel Index (MBI) for ability of daily living were used for assessment of the therapeutic effect. RESULTS: After treatment, the spasm was significantly alleviated, the motor function of the upper limb and daily living ability were significantly increased (P<0.01) in the two groups; after treatment, BMI scores in the acupuncture group was very significantly superior to that in the electro-stimulation group. The total effective rate was 93.3% in the acupuncture group and 86.7% in the electro-stimulation group, with no significant difference between the two groups. CONCLUSION: Proper acupuncture is an effective method for upper limb spasm in the patient of poststroke, and the therapeutic effect is better for mild-moderate spasm of the upper limb.