Functional analysis of NopM, a novel E3 ubiquitin ligase (NEL) domain effector of Rhizobium sp. strain NGR234.

Type 3 effector proteins secreted via the bacterial type 3 secretion system (T3SS) are not only virulence factors of pathogenic bacteria, but also influence symbiotic interactions between nitrogen-fixing nodule bacteria (rhizobia) and leguminous host plants. In this study, we characterized NopM (nodulation outer protein M) of Rhizobium sp. strain NGR234, which shows sequence similarities with novel E3 ubiquitin ligase (NEL) domain effectors from the human pathogens Shigella flexneri and Salomonella enterica. NopM expressed in Escherichia coli, but not the non-functional mutant protein NopM-C338A, showed E3 ubiquitin ligase activity in vitro. In vivo, NopM, but not inactive NopM-C338A, promoted nodulation of the host plant Lablab purpureus by NGR234. When NopM was expressed in yeast, it inhibited mating pheromone signaling, a mitogen-activated protein (MAP) kinase pathway. When expressed in the plant Nicotiana benthamiana, NopM inhibited one part of the plant's defense response, as shown by a reduced production of reactive oxygen species (ROS) in response to the flagellin peptide flg22, whereas it stimulated another part, namely the induction of defense genes. In summary, our data indicate the potential for NopM as a functional NEL domain E3 ubiquitin ligase. Our findings that NopM dampened the flg22-induced ROS burst in N. benthamiana but promoted defense gene induction are consistent with the concept that pattern-triggered immunity is split in two separate signaling branches, one leading to ROS production and the other to defense gene induction.

Dissection of genetic overlap of drought and low-temperature tolerance QTLs at the germination stage using backcross introgression lines in soybean.

Northeast of China is the main soybean production area, drought and low-temperature tolerance are both main factors involved in reducing soybean yield and limiting planting regions, the most effective way to solve this problem is to breed cultivars with drought and low-temperature tolerance. A set of the BC(2)F(3) lines was constructed with Hongfeng 11 as recurrent parent and Harosoy as donor parent, and screened in drought and low-temperature condition at the germination stage. Related QTLs were obtained by Chi-test and ANOVA analysis with genotypic and phenotypic data. Eighteen QTLs of drought tolerance and 23 QTLs of low-temperature tolerance were detected. Among them, 12 QTLs were correlated with both drought and low-temperature tolerance, which showed a partial genetic overlap between drought and low-temperature tolerance at the germination stage in soybean. Among the 12 genetic overlap QTLs, Satt253, Satt513, Satt693, Satt240, Satt323, and Satt255 were detected by at least one method for both drought and low-temperature tolerance. Satt557, Satt452, Sat_331, Satt338, Satt271, and Satt588 were detected by only one analysis method. The QTLs detected above were significant loci for drought or low-temperature tolerance in soybean. This will play an important role in MAS for development of both drought and low-temperature tolerance variety.

Multi-environment mapping and meta-analysis of 100-seed weight in soybean.

100-Seed weight (100-SW) of soybean is an important but complicated quantitative trait to yield. This study was focus on the quantitative trait loci (QTLs) of soybean 100-SW from 2006 to 2010, using recombination inbred lines population that was derived from a cross between Charleston and Dongnong 594. A total of 23 QTLs for 100-SW were detected in the linkage group C2, D1a, F, G and O. Nine QTLs were identified by composite interval mapping including one QTL with the minimum confidence interval (CI) of 1.3 cM, while 14 QTLs by multiple interval mapping. Furthermore, 94 reported QTLs of 100-SW were integrated with our QTL mapping results using BioMercator. As a result, 15 consensus QTLs and their corresponding markers were identified. The minimum CI was reduced to 1.52 cM by the combination of meta-analysis. These findings may merit fine-mapping of these QTL in soybean.

Analysis of miRNAs Targeted Storage Regulatory Genes during Soybean Seed Development Based on Transcriptome Sequencing.

Soybeans are an important cash crop and are widely used as a source of vegetable protein and edible oil. MicroRNAs (miRNA) are endogenous small RNA that play an important regulatory role in the evolutionarily conserved system of gene expression. In this study, we selected four lines with extreme phenotypes, as well as high or low protein and oil content, from the chromosome segment substitution line (CSSL) constructed from suinong (SN14) and ZYD00006, and planted and sampled at three stages of grain development for small RNA sequencing and expression analysis. The sequencing results revealed the expression pattern of miRNA in the materials, and predicted miRNA-targeted regulatory genes, including 1967 pairs of corresponding relationships between known-miRNA and their target genes, as well as 597 pairs of corresponding relationships between novel-miRNA and their target genes. After screening and annotating genes that were targeted for regulation, five specific genes were identified to be differentially expressed during seed development and subsequently analyzed for their regulatory relationship with miRNAs. The expression pattern of the targeted gene was verified by Real-time Quantitative PCR (RT-qPCR). Our research provides more information about the miRNA regulatory network in soybeans and further identifies useful genes that regulate storage during soy grain development, providing a theoretical basis for the regulation of soybean quality traits.

ß­Ecdysterone promotes autophagy and inhibits apoptosis in osteoporotic rats.

Osteoporosis is an aging process of skeletal tissues with characteristics of reductions in bone mass and microarchitectural deterioration of bone tissue. The present study aimed to investigate the effects of glucocorticoid­induced osteoporosis on osteoblasts and to examine the roles of ß­ecdysterone (ß­Ecd) involved. In the present study, an in vivo model of osteoporosis was established through the subcutaneous implantation of prednisolone (PRED) into Sprague­Dawley rats, with or without a subcutaneous injection of ß­Ecd (5 or 10 mg/kg body weight). Expression of Beclin­1 and microtubule­associated protein 1A/1B­light chain 3I/II and apoptosis in lumbar vertebrae tissues was measured by immunofluorescence and TUNEL assays, respectively. Serum concentration of calcium and phosphorus, and the activity of tartrate­resistant acid phosphatase (TRAP) and alkaline phosphatase (ALP) were measured by biochemical assay. Reverse transcription­quantitative polymerase chain reaction and western blotting was used for detect the expression of related genes and proteins. PRED treatment inhibited bone formation by decreasing bone mineral density, and suppressing the expression of Runt­related transcription factor 2 and bone morphogenetic protein 2, while enhancing the activity of alkaline phosphatase, upregulating the expression of receptor activator of nuclear factor-κB ligand, and increasing the serum content of calcium, phosphorus and tartrate­resistant acid phosphatase in rats. Additionally, PRED was revealed to inhibit autophagy through the downregulation of Beclin­1, autophagy protein 5 and microtubule­associated protein 1A/1B­light chain 3I/II expression, whereas it induced the apoptosis, through the activation of caspase­3 and the suppression of apoptosis regulator BCL2 expression. Notably, the PRED­induced alterations in bone formation, autophagy and apoptosis were revealed to be attenuated by ß­Ecd administration. In conclusion, the findings of the present study suggested that ß­Ecd may be a promising candidate for the development of therapeutic strategies for the treatment of osteoporosis, through the induction of autophagy and the inhibition of apoptosis in vivo.

Effect of ß­ecdysterone on glucocorticoid­induced apoptosis and autophagy in osteoblasts.

The aim of the present study was to investigate the effect of glucocorticoids in osteoblasts and to examine the role of ß­ecdysterone in the pathogenesis of glucocorticoid­induced osteoporosis. Osteoblasts were induced from bone marrow mesenchymal stem cells, which were isolated from C57BL/6 mice. Cell viability and apoptosis of osteoblasts were measured by Cell Counting Kit­8 and flow cytometry analysis, respectively. The expression of related genes and proteins was measured by reverse transcription quantitative polymerase chain reaction and western blot analysis respectively. Dose­dependent decreases in the cell proliferation and differentiation were observed in dexamethasone (Dex)­treated osteoblasts, evidenced by downregulation in the activity of alkaline phosphatasedecreased expression levels of Runt­related transcription factor 2 and osteocalcin, and upregulated expression of RANK ligand. Dex also induced apoptosis and inhibited autophagy of osteoblasts, evidenced by upregulated B­cell lymphoma 2 (Bcl­2)­associated X protein/Bcl­2 ratio and the activation of mammalian target of rapamycin (mTOR), and decreased expression levels of Beclin­1, autophagy protein 5 and microtubule­associated protein 1 light chain 3 II. The effects on cell proliferation, apoptosis and autophagy induced by Dex were reversed by ß­ecdysterone in a dose­dependent manner. Therefore, ß­ecdysterone may be a promising candidate drug for the treatment of osteoporosis through inducing osteoblast autophagic activity by inactivating mTOR.

[Surgical treatment for open tarsometatarsal joint injury].

OBJECTIVE: To discuss the surgical method and clinical efficacy for open tarsometatarsal joint injuries. METHODS: From March 2011 to January 2015, 21 patients with open tarsometatarsal joint injuries were treated with stage-surgery method, including 14 males and 7 females with an average age of 45.6 years old ranging from 20 to 75 years. Injury site occurred in the left foot of 13 cases and right foot of 8 cases. Traffic injury was in 5 cases, crush injury in 6 cases, heavy crushing was in 10 cases. According to Myerson to classify for tarsometatarsal joint injury, 5 cases were type B2, 9 cases were type C1, and 7 cases were type C2. And according to Gustilo to typing for soft tissue injury, 5 cases were type IIB, 10 cases were type IIIA, 6 cases were type IIIB. Fracture healingand complications were observed after operation and clinical effects were evaluated according to the midfoot score of AOFAS. RESULTS: All the patients were followed up from 11 to 40 months with an average of 16.2 months. The fracture healing time was from 10 to 16 weeks with an average of 12.3 weeks. No complications such as deep infection, nonunion and osteomyelitis were found. Midfoot score of AOFAS at last follow-up was 83.0±14.9, 9 cases got excellent results, 8 good, 2 fair, 2 poor. Two patients complicated with severe traumatic arthritis once again underwent tarsometatarsal arthrodesis. CONCLUSIONS: For the treatment of open tarsometatarsal joint injury, reasonable debridement, comprehensive assessment for the soft tissue injury, correctly grasp the surgical indications and time of internal fixation, can reduce the incidence of deep infection and osteomyelitis.

[Iindividual choice of distal fibula internal fixation for ankle fractures in elderly].

OBJECTIVE: To explore individual choice and therapeutic effect of distal fibula internal fixation in treating ankle fractures in elderly. METHODS: From May 2012 to April 2015, 68 elderly patients with ankle fractures were treated by surgical operation, included 37 males and 31 females with an average of 69.2 years old ranging from 62 to 81 years. According to Danis-Weber classification, there were 19 cases belong to type A, 31 cases belong to type B, and 18 cases belong to type C. According to Lange-Hanson classification, 22 cases were supinatio-extorsion, 18 were pronate-extorsion, 19 were supinatio-adduction, and 9 were pronate-abduction. All patients were performed individyually with different internal fixation methods for the treatment of distal fibula fracture according to different types of fracture. Clinical results were evaluated based on clinical examination, radiographic evaluation and AOFAS score. RESULTS: Twelve patients were treated with Herbert screw, 7 cases with Kirschner wire tension band, 5 cases with 1/3 tube plate, 6 cases with reconstruction plate, 17 cases with fibular end dissection steel plate composite, and 21 cases with distal fibula anatomic locking plate. All patients were followed up from 12 to 26 months with an average of 17.7 months. The operative incision of all patients were primary healed. And there was no bone nonunion, ankle instability, internal fixation loosening and fracture occurred. Fracture healing time ranged from 2.7 to 4 months with an average of 3.2 months, and had significant differences among different groups(P<0.05). There were no statistical differences in AOFAS score, VAS score and motion of ankle joint among different internal fixation groups(P>0.05). Dorsal stretch was 6° to 18° with an average of 15°, plantar flexion ranged from 26°to 47° with an average of 37°. AOFAS score at the latest following-up was 88.4±4.3, 34 patients got an excellent result, 30 good and 4 fair. CONCLUSIONS: Good clinical results could be obtained by using individualized internal fixation for distal fibula fracture for the treatment of the ankle fractures in elderly.

[Clinical application of free vascularized flaps based on the wrist cutaneous branch of ulnar artery in repairing finger soft tissue defect].

OBJECTIVE: To investigate the methods and clinical effects of repairing finger soft tissue defect with free vascularized flaps based on the wrist cutaneous branch of ulnar artery. METHODS: From February 2010 to December 2012, 16 patients with finger soft tissue defects were repaired by free vascularized flaps based on the wrist cutaneous branch of ulnar artery, including 10 males and 6 females with an average age of 38.2 years old ranging from 18 to 52 years. Among them, 5 cases caused by hot crush injury, 8 cases caused by machine crush injury, 3 cases caused by firecracker burst injury. The defect area varied from 1.3 cm x 2.3 cm to 2.6 cm x 5.0 cm. The flap area varied from 1.5 cm x 2.5 cm to 2.8 cm x 5.2 cm. The appearance and two-point discrimination of flap were observed after operation. RESULTS: All flaps survived and wounds healed primarily. No wound infection and skin necrosis were found in donor site and recipient site. Among repair methods, direct suture in forearm donor site had 11 cases and skin graft had 5 cases. All patients were followed up from 6 to 24 months with an average of 10.8 months. The appearance of flap was not fat or clumsy, texture and color were similar to the recipient site, the sensation were good, two-point discrimination was 6 to 9 mm. The appearance of donor site were well complicated with mild scarring without dysfunction obviously. CONCLUSION: The free vascularized flaps based on the wrist cutaneous branch of ulnar artery has the advantages of vascular anatomy constant,thickness moderate and carry sensory nerves, etc, which is effective way to repair finger soft tissue defects.

[Staple fixation for the treatment of hamate metacarpal joint injury].

OBJECTIVE: To investigate the effcacy of the staple fixation for the treatment of hamate metacarpal joint injury. METHODS: From May 2009 to November 2012,16 patients with hamate metacarpal joint injury were treated with staple fixation including 10 males and 6 females with an average age of 33.6 years old ranging from 21 to 57 years. Among them, 11 cases were on the fourth or fifth metacarpal base dislocation without fractures, 5 cases were the fourth or fifth metacarpal base dislocation with avulsion fractures of the back of hamatum. Regular X-ray review was used to observe the fracture healing, joint replacement and position of staple fixation. The function of carpometacarpal joint and metacarpophalangeal joint were evaluated according to ASIA (TAM) system evaluation method. RESULTS: All incision were healed well with no infection. All patients were followed up from 16 to 24 months with an average of (10.0 +/- 2.7) months. No dislocation recurred, the position of internal fixator was good,no broken nail and screw withdrawal were occurred. Five patients with avulsion fracture of the back of hamatum achieved bone healing. The function of carpometacarpal joint and metacarpophalangeal was excellent in 10 cases,good in 5 cases, moderate in 1 case. CONCLUSION: The application of the staple for the treatment of hamatometacarpal joint injury has the advantages of simple operation, small trauma, reliable fixation, early postoperative function exercise and other advantages, which is the ideal operation mode for hamatometacarpal joint injury.

[Construction and primary analysis of subtractive library induced by soybean mosaic virus (SMV)].

SMV is one of main diseases of soybean, which could affect yields and quality of soybean seriously. It was effective to soybean breeding by studying the expression of resistant gene to SMV with molecular technology. In this study, a soybean resistance line, DongNong 8143, was used to construct a subtractive cDNA library by SSH from soybean leaves inoculated by SMV No.1 at primary stage. cDNA dominantly or specifically expressed in infected leaves was purified using PCR Purification Kit and cloned into pGEM-T easy vector. Colonies were grown on LB-agar plates containing ampicillin, X-gal and IPTG. A subtractive plasmid library was constructed by SSH. Then the library was transformed to host bacteria E. coli DH5alpha, and the titer of the library was measured as 2 x 10(3) . 64 clones were picked up randomly and sequenced. Of them there is 50 clones which result of sequenced were good. The length of EST fragment varied from 136bp to 691bp, and the average length is 456bp. Among them, 41 sequences has poly(A). Through ESTs were compared with sequences in unigene database of GeneBank with BLASTn and BLASTx algorithm, 38 ESTs of them had comparatively clear results and the percent of them in acquired ESTs is 74%. The EST expression profile showed that the resistance-related genes include cell protection, signal transduction, restrict pathogen growth, system acquired resistance, and house-keeping gene. There are 12 ESTs, which have not comparatively clear results, that maybe new genes.