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Foamy viruses belong to the Spumaretrovirinae subfamily member of the Retroviridae family and produce nonpathogenic infection to hosts in the natural conditions. However, infections of foamy viruses can dramatically cause severe cytopathic effects in vitro. To date, the exact molecular mechanism has remained unclear which implied the tremendous importance of virus-host cell immune reactions. In this study, we found that the transactivator Tas in two foamy viruses isolated from Old World Monkey (OWM) induced obvious inhibition of cell proliferation via the upregulation of Foxo3a expression. It was mediated by the generation of ROS and the initiation of ER stress, and ultimately, the mitochondrial apoptosis pathway was triggered. Notably, PFV Tas contributed to the accumulation of G0/G1 phase cycle arrest induced by the activation of the p53 signaling pathway and the nuclear transportation of HDAC4 via upregulating PPM1E expression. Together, these results demonstrated the different survival strategies by which foamy virus can hijack host cell cytokines and regulate virus-host cell interactions.

Mitochondria are structurally and functionally unique organelles in male gametes. Apparently, as the only organelles remaining in mature sperm, mitochondria not only produce adeno-sine triphosphate (ATP) through oxidative phosphorylation (OXPHOS) to support sperm mobility, but also play key roles in regulating reactive oxidation species (ROS) signaling, calcium homeostasis, steroid hormone biosynthesis, and apoptosis. Mitochondrial dysfunction is often associated with the aging process. Age-dependent alterations of the epididymis can cause alterations in sperm mitochondrial functioning. The resultant cellular defects in sperm have been implicated in male infertility. Among these, oxidative stress (OS) due to the overproduction of ROS in mitochondria may represent one of the major causes of these disorders. Excessive ROS can trigger DNA damage, disturb calcium homeostasis, impair OXPHOS, disrupt the integrity of the sperm lipid membrane, and induce apoptosis. Given these facts, scavenging ROS by antioxidants hold great potential in terms of finding promising therapeutic strategies to treat male infertility. Here, we summarize the progress made in understanding mitochondrial dysfunction, aging, and male infertility. The clinical potential of antioxidant interventions was also discussed. [ABSTRACT FROM AUTHOR]

In the present study, Sargassum fusiforme was used as the raw materials, and the physicochemical properties and probiotic activity of its polysaccharides extracted by hot water extraction, ultrasonic-assisted water extraction, pulsed electric field-assisted water extraction and cellulase-assisted water extraction were examined. Firstly, the yield, molecular weight, monosaccharide composition and rheological properties of the four polysaccharides were determined. Then, the four polysaccharides were added to the fermentation medium of Lactobacillus to replace glucose as the carbon source for in vitro fermentation to evaluate its ability to promote the proliferation activity of Lactobacillus. The results showed that the yield of the polysaccharide obtained by the cellulase-assisted water extraction (E-SFP) was the highest (14.02%), followed by ultrasonic-assisted water extraction (U-SFP; 12.57%), pulse-assisted water extraction (P-SFP; 10.38%) and hot-water extraction (SFP; 7.07%). The four polysaccharides had an average molecular weight ranging from 200 to 245 ku, and consisted mainly of fucose, glucose, galactose, mannose and xylose, with the content of glucose in E-SFP (19.57%) higher than those of the other three polysaccharides. The solutions of the four polysaccharides were typical non-Newtonian fluids, and their apparent viscosities were positively correlated with their molecular weights. Compared with the blank group, four polysaccharides were found to promote the proliferation of Lactobacillus, among which E-SFP had a significantly greater proliferation-promoting effect than the other three polysaccharides (p<0.05) (fermentation for 48 h, OD600 value up to 0.50). Comprehensive comparisons revealed that the polysaccharides obtained by the cellulase-assisted water extraction method had the highest yield and strongest proliferation activity on Lactobacillus. The results of this study can provide reference for the preparation of polysaccharides from Sargassumfusiforme and studies on their prebiotic properties. [ABSTRACT FROM AUTHOR]

The MYB proteins comprise one of the largest families of transcription factors (TFs) in plants. Although several MYB genes have been characterized to play roles in secondary metabolism, the MYB family has not yet been identified in apple. In this study, 229 apple MYB genes were identified through a genome-wide analysis and divided into 45 subgroups. A computational analysis was conducted using the apple genomic database to yield a complete overview of the MYB family, including the intron-exon organizations, the sequence features of the MYB DNA-binding domains, the carboxy-terminal motifs, and the chromosomal locations. Subsequently, the expression of 18 MYB genes, including 12 were chosen from stress-related subgroups, while another 6 ones from other subgroups, in response to various abiotic stresses was examined. It was found that several of these MYB genes, particularly MdoMYB121, were induced by multiple stresses. The MdoMYB121 was then further functionally characterized. Its predicted protein was found to be localized in the nucleus. A transgenic analysis indicated that the overexpression of the MdoMYB121 gene remarkably enhanced the tolerance to high salinity, drought, and cold stresses in transgenic tomato and apple plants. Our results indicate that the MYB genes are highly conserved in plant species and that MdoMYB121 can be used as a target gene in genetic engineering approaches to improve the tolerance of plants to multiple abiotic stresses. [ABSTRACT FROM AUTHOR]

Objective To assess and compare the Human Papillomavirus (HPV) detection efficiency and the potential clinical utility of PCR sequencing-based technology. Methods Four HPV consensus primer sets (GP5+/6+, MGP, MY09/11, and PGMY09/11) were used in order to amplify a broad spectrum of HPV types for HPV infection in 325 cervical samples and the PCR products were sequenced afterwards for the HPV genotyping. Results The HPV-positive rate was 75.4%, of which 35.5% harbored more than one HPV genotype. A total of 36 different genotypes was found, with HPV 16 (24.1%) being the most prevalent, followed by HPV 58 (13.3%) and HPV 52 (9.6%). There were substantial to almost perfect agreements between different primer sets regarding HPV detection efficiency, with the kappa value varying from 0.751 to 0.925, MGP, and PGMY09/11 were the most effective in detecting multiple infections (P<0.001). With each of the primer sets, a board range of HPV types could be identified, though there were several differences for a few genotypes. Conclusion The substantial agreement between PCR-sequencing and HC2 for the detection of high-risk HPV (kappa=0.761) indicated that PCR-sequencing is also suitable for routine HPV screening. [ABSTRACT FROM AUTHOR]

SIZ1 (a SIZ/PIAS-type SUMO E3 ligase)-mediated small ubiquitin-like modifier (SUMO) modification of target proteins is important for various biological processes related to abiotic stress resistance in plants; however, little is known about its role in resistance toward iron (Fe) deficiency. Here, the SUMO E3 ligase MdSIZ1 was shown to be involved in the plasma membrane (PM) H + -ATPase-mediated response to Fe deficiency. Subsequently, a basic helix-loop-helix transcription factor, MdbHLH104 (a homolog of Arabidopsis bHLH104 in apple), which acts as a key component in regulating PM H + -ATPase-mediated rhizosphere acidification and Fe uptake in apples ( Malus domestica ), was identified as a direct target of MdSIZ1. MdSIZ1 directly sumoylated MdbHLH104 both in vitro and in vivo, especially under conditions of Fe deficiency, and this sumoylation was required for MdbHLH104 protein stability. Double substitution of K139R and K153R in MdbHLH104 blocked MdSIZ1-mediated sumoylation in vitro and in vivo, indicating that the K139 and K153 residues were the principal sites of SUMO conjugation. Moreover, the transcript level of the MdSIZ1 gene was substantially induced following Fe deficiency. MdSIZ1 overexpression exerted a positive influence on PM H + -ATPase-mediated rhizosphere acidification and Fe uptake. Our findings reveal an important role for sumoylation in the regulation of PM H + -ATPase-mediated rhizosphere acidification and Fe uptake during Fe deficiency in plants., (© 2019 American Society of Plant Biologists. All rights reserved.)

Objective: To investigate the association between viral load, genomic integration frequency of HPV 16 and cervical carcinogenesis and assess the probability that HPV 16 integration frequency may be utilized as a marker for cervical cancer., Methods: Forty cases of HPV16 single infection were selected from 337 cervical scrape samples by PCR (polymerase chain reaction) amplification and DNA sequencing. The copy numbers of E2, E6 and β-actin were quantified to evaluate the viral load and integration status by real-time PCR., Results: (1) The median number of adjusted viral load of normal group, LSIL (low-grade squamous intraepithelial lesion) group, HSIL (high-grade squamous intraepithelial lesion) group and squamous cervical cancer group were 0.11, 18.55, 44.63 and 7.6 copies per cell respectively. The viral load was higher in LSIL-HSIL group than that in normal group while lower in squamous cervical cancer group than that in HSIL group. (2) The median number of E2/E6 was 0.93 in normal group, 0.84 in precancerous group (LSIL-HSIL) and 0.64 in squamous cervical cancer group respectively. It showed a descending trend with the progression of cervical disease. (3) With the disease development, the proportion of episomal form decreased (normal group 4/5, LSIL group 4/6, HSIL group 10/16, cervical squamous cancer group 5/13) whereas that of integrated form (mixed and totally integrated) increased (normal group 1/5, LSIL group 2/6, HSIL group 6/16, cervical squamous cancer group 8/13). Both totally integrated cases were cervical squamous cancer., Conclusion: (1) HPV 16 viral load may not be an ideal marker to predict cervical carcinogenesis. (2) Due to a positive correlation between HPV16 genomic integration frequency and cervical neoplastic progression, HPV 16 integration frequency may be a potential marker of early diagnosis for cervical lesion progression.