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Sugarcane, a vital cash crop, contributes significantly to the world's sugar supply and raw materials for biofuel production, playing a significant role in the global sugar industry. However, sustainable productivity is severely hampered by biotic and abiotic stressors. Genetic engineering has been used to transfer useful genes into sugarcane plants to improve desirable traits and has emerged as a basic and applied research method to maintain growth and productivity under different adverse environmental conditions. However, the use of transgenic approaches remains contentious and requires rigorous experimental methods to address biosafety challenges. Clustered regularly interspaced short palindromic repeat (CRISPR) mediated genome editing technology is growing rapidly and may revolutionize sugarcane production. This review aims to explore innovative genetic engineering techniques and their successful application in developing sugarcane cultivars with enhanced resistance to biotic and abiotic stresses to produce superior sugarcane cultivars. [ABSTRACT FROM AUTHOR]

Cane yield and sucrose content are the two main breeding objectives in sugarcane, and plant height, stem diameter, and brix are major constituent factors of cane yield and sucrose. Identification of associated molecular markers and exploring elite alleles with yield and sucrose traits could provide a theoretical basis and reference for marker assisted breeding of sugarcane. In this study, 62 sugarcane germplasm entries were used as the experimental materials. Three breeding traits, including plant height, stem diameter, and brix were investigated under four planting environments at maturity stage. ANOVA, genetic variation analysis and association analysis between the identified from related markers for further allele effect analysis. The result of ANOVA revealed that genotype, planting environment and their interaction had significant effect on plant height, stem diameter and brix in sugarcane. The broad-sense heritability of the three traits ranged from 0.68 to 0.76, indicating that they had stable genetic characteristics and their phenotype was mainly determined by its genotype. The frequency of these three traits showed typical quantitative traits with normal distribution characteristics. The coefficients of variation of the three traits ranged from 6.73% to 19.89%, suggesting a rich variation in phenotypes. A total of 204 alleles were found with a mean of 5.5135 per marker. The average gene diversity coefficient was 0.6779, and the average PIC value was 0.6252. The 89.19% of total markers were highly polymorphic with PIC>0.5. Population structure analysis revealed that the tested group could be divided into three subgroups. A total of 20 markers were detected associated with plant height, stem diameter, and brix traits based on MLM method, which explained 5.04%--27.98% of phenotypic variation. Seven of them detected in two or more planting environments were considered as elite markers, 8 alleles with positive effect were identified and considered as the elite alleles, and 10 typical materials were found carrying these elite alleles by allele effect analysis. These results provide a great significance for candidate gene mining of yield and sucrose content traits and parents selection of hybrid combinations in sugarcane breeding. [ABSTRACT FROM AUTHOR]

Tillering is one of the most important agronomic traits for sugarcane which is a vegetatively propagated economic crop. Mining these genes related to tillering trait and utilizing them form an ideal architecture are important to effectively increase cane yield of sugarcane varieties. In this study, qRT-PCR technology was used to explore the expression characteristics of a homologue of HTD2 related to rice tillering, which was named ScHTD2 previously obtained from sugarcane. The polymorphism of ScHTD2 gene in sugarcane germplasm resource population was analyzed, and the correlation between variation sites and tillering trait were also detected. The results showed that relative expression of this gene was tissue specific and highest in leaves. During the germination and development of axillary, the relative expression was the highest in the dormant buds. With the germination of sugar buds, the relative expression level first was significantly down-regulated, and the germination and development of sugar buds were negatively regulated. Treatments of phytokinin, auxin and strigolactone can significantly induce its expression in germinating axillary buds and tiller buds of seedling. By combining with the phenotypic changes after hormone treatment, the high expression of this gene induced auxin and strigolactone could inhibit the continued development of germinating axillary buds and delay the occurrence of tillers, but this inhibitory effect did not occur in the high expression of this gene induced by phytokines. Gene polymorphism analysis on 520 cloned sequences of HTD2 genomic DNA from 26 sugarcane germplasm resources showed that the genome sequence structure of this gene contained two exons and one intron, and the variation was the most abundant in the intron region, followed by the exon 1 region. Much higher nucleotide diversity in intron region was detected in main sugarcane variety population, while the origin species parent population had the higher nucleotide diversity in exon 1 and 2 regions. In terms of haplotype diversity in the coding region, the origin species parent population possessed the most abundant haplotype diversity, followed by the main variety population. In the genetic selectivity test, the original species parent population was subjected to positive selection, with high selection pressure and rapid gene evolution, while the backbone parents population and the main variety populations are subject to negative selection toward purification. Two haplotypes of code region located at radiating center of haplotype evolution map, indicating that they belonged to primitive types. The dose effect of mutation type from 23 SNP sites and 5 InDel sites in the code region was significantly related to the tillering rate of sugarcane germplasm resources, so more attention should be paid to the dose effect of mutation types in sugarcane molecular assisted-breeding plan in future. The present study lays a foundation for further analyzing the biological meaning of tillering related to key genes and the development of functional markers in sugarcane. [ABSTRACT FROM AUTHOR]

The C2H2 zinc finger protein family, one of the largest families of transcription factor/transcriptional regulator in mammal, arose from a small ancestral group of eukaryotic zinc finger transcription factors through many repeated gene duplications accompanied by functional divergence. As the biggest subfamily of C2H2 zinc finger protein family, Kruppel-associated box-containing zinc finger proteins (KRAB-ZFPs) appeared at the period oftetrapod, expand rapidly along with species evolution, and take about 60% of the total C2H2 zinc finger proteins in human. During species evolution, the DNA binding ability of KRAB-ZFPs is changed while the KRAB-ZFPs-mediate transcriptional repression ability maintains stable under the evolution pressure. Moreover, multiple KRAB-ZFPs function synergistically with KAP1 on transcriptional silencing of retroelements, and the coevolution between KRAB-ZFPs and target retrotransposons restrict the jumping ability of the retroelements. In this review, we summarize the roles of KRAB-ZFPs duplication, the flexibility of zinc finger structure, transcriptional repression of KRAB-ZFPs/KAP1 and retroelement "jump" in promoting the divergence in regulatory network, stable genome change and species evolution, in order to reveal the characters and functions of KRAB-ZFPs in driving species evolution stably.

Chronic obstructive pulmonary disease (COPD) is a common respiratory disease, but seriously threatens to patients' body and mind. Constitutions of Chinese medicine (CM) are closely relat- ed to diseases. Individuals with different constitutions of CM have different responses to the same envi- ronment and the same pathogenic factor. Therefore, studying the application of constitution theory of CM in stable phase COPD is of great significance. In this paper clinical applications of constitution theory of CM in COPD were explored from etiology and mechanism, syndrome typing based treatment, prevention and care, aiming to prevent, diagnose, and treat COPD effectively.

The asymmetric unit of the title compound, [Co(N(3))(2)(H(2)O)(4)]·C(14)H(12)N(2)O(4), comprises half of the cobalt(II) complex mol-ecule and a half of the 3,3'-dicarboxyl-ato-1,1'-ethyl-enedipyridinium mol-ecule. The Co(II) atom is located on an inversion centre and hence the complex mol-ecule adopts a centrosymmetric trans-octa-hedral geometry. The zwitterionic organic mol-ecule is also centrosymmetric with the centre of the C-C bond of the ethyl-ene moiety coinciding with an inversion centre. The adduct of metal complex and organic mol-ecule is associated into a three-dimenional network through O-H⋯O hydrogen bonds.

The ubiquitin protein ligase (E3) MDM2 (Murine double minute 2) possesses oncogenic activities. Overexpression of this protein enhances degradation and inactivation of the tumor suppressor p53. At least 7% of all human tumors exhibit inappropriate amplification of mdm2, whereas p53 gene remains in its wild-type configuration. This indicates that MDM2 may function in the p53-independent manner to promote tumorigenesis. Considering the critical role of MDM2, this review summarizes the current mechanisms and progress on MDM2 regulation in levels of gene control, mRNA transcription, post-translational modification, and interaction proteins.

Site- and state-specific lysine methylation of histones is catalyzed by a family of proteins including those contain the evolutionarily conserved SET domain. Research on histone methyltransferases is a part of epigenetics, which plays a fundamental role in heterochromatin formation, X-chromosome inactivation and transcription regulation. Aberrant histone methylation was linked to a number of developmental disorders and human disease including several carcinomas. Histone lysine methylation is a functionally complex process, as it can either activate or repress transcription, depending on sequence-specific lysine methylation site in histones. Non-histone proteins were found to be methylated by SET domain-containing histone methyltransferases whose primary targets were presumed to be histones. The researches on histone methyltransferases will make a completely new space for transcriptional activity, embryonic development, cell differentiation, and signal transduction.

The zinc finger proteins containing the Kruppel-associated box domain (KRAB) constitute the largest single family of transcriptional regulators in mammals. Many genes encoding members of this family are arranged in clusters. KRAB-containing proteins are characterized by the presence of 4 and over 30 C2H2 zinc-finger motifs and a KRAB domain near the amino terminus of the protein. KRAB domain behaving as a protein-protein interaction domain could bind to corepressor proteins and/or transcription factors, and that the KRAB-containing proteins could act as a repressor or corepressor and play a key role in transcriptional repression. Members of the family are involved in embryonic development, cell differentiation, cell proliferation, apoptosis, neoplastic transformation and cell cycle regulation.

To examine the binding sites of miyabenol C (Miy C) and kobophenol A ( Kob A) with estrogen receptor (ER), computer modeling was applied to determine 3D structure of Miy C and Kob A. Molecular docking of the components to ER was carried out to find the binding sites between them. PCR mutagenesis was used to change the structure of ER cDNA. After the mutated sites were confirmed by DNA sequencing, report gene assay was used to study the effects of Miy C and Kob A on the trans-activating ability of ER. Results indicated that the effect of Miy C on the trans-activating ability of mutant 1 of ER [M1ER (ER M(517)AG(521)D)] was decreased, and Kob A had no stimulating effects on the trans-activating ability of M1ER. Miy C and Kob A had no stimulating effects on the trans-activating ability of mutant 2 of ER [M2ER (ER E(353)GR(394)G)]. Therefore, the ER sites for Miy C and Kob A may be located at Glu(353), Arg(394), Met(517) and Gly(521).

Aim: To improve E-screen assay and make it more accurate to screen estrogenic compounds., Methods: Estrogen receptor antisense RNA expression plasmid (pCASER) was constructed and introduced into MCF-7 with lipofectAMINE(TM), and positive clones were screened out with G418. PCR amplification was employed to identify whether estrogen receptor (ER) cDNA fragment had been inserted into MCF-7 cell genomes. Western blot was applied to detect the expression of ER. Cell growth was determined by MTT assay., Results: One ER antisense clone (MTASER) had been screened out. The effects of 17beta-estradiol, genistein, droloxifen, miyabenol C, and kobophenol A on MCF-7 were stronger than those effects on MTASER. Epidermal growth factor (EGF) had equivalent stimulatory effects on the proliferation of MCF-7 and MTASER., Conclusion: The improved E-screen assay could screen estrogenic compounds more accurately than original E-screen assay did.