A major difference between the divergence patterns within the lines-1 families in mice and voles

L1 retroposons are represented in mice by subfamilies of interspersed sequences of varied abundance. Previous analyses have indicated that subfamilies are generated by duplicative transposition of a small number of members of the L1 family, the progeny of which then become a major component of the murine L1 population, and are not due to any active processes generating homology within preexisting groups of elements in a particular species. In mice, more than a third of the L1 elements belong to a clade that became active approximately 5 Mya and whose elements are > or = 95% identical. We have collected sequence information from 13 L1 elements isolated from two species of voles (Rodentia: Microtinae: Microtus and Arvicola) and have found that divergence within the vole L1 population is quite different from that in mice, in that there is no abundant subfamily of homologous elements. Individual L1 elements from voles are very divergent from one another and belong to a clade that began a period of elevated duplicative transposition approximately 13 Mya. Sequence analyses of portions of these divergent L1 elements (approximately 250 bp each) gave no evidence for concerted evolution having acted on the vole L1 elements since the split of the two vole lineages approximately 3.5 Mya; that is, the observed interspecific divergence (6.7%-24.7%) is not larger than the intraspecific divergence (7.9%-27.2%), and phylogenetic analyses showed no clustering into Arvicola and Microtus clades.      

Multifactorial diversity sustains microbial community stability

Maintenance of a high degree of biodiversity in homogeneous environments is poorly understood. A complex cheese starter culture with a long history of use was characterized as a model system to study simple microbial communities. Eight distinct genetic lineages were identified, encompassing two species: Lactococcus lactis and Leuconostoc mesenteroides. The genetic lineages were found to be collections of strains with variable plasmid content and phage sensitivities. Kill-the-winner hypothesis explaining the suppression of the fittest strains by density-dependent phage predation was operational at the strain level. This prevents the eradication of entire genetic lineages from the community during propagation regimes (back-slopping), stabilizing the genetic heterogeneity in the starter culture against environmental uncertainty.     

Immunohistochemical localization of irisin in skin,eye, and thyroid and pineal glands of the crested porcupine (Hystrix cristata)

Irisin was first identified in muscle cells. We detected irisin immunoreactivity in various organs of the crested porcupine (Hystrix cristata). In the epidermis, irisin immunoreactivity was localized mainly in stratum basale, stratum spinosum and stratum granulosum layers; immunoreactivity was not observed in the stratum corneum. In the dermis, irisin was found in the external and internal root sheath, cortex and medulla of hair follicles, and in sebaceous glands. Irisin immunoreactivity was found in the neural retina and skeletal muscle fibers associated with the eye. The pineal and thyroid glands also exhibited irisin immunoreactivity.     

An electrochemical biosensor for prostate cancer biomarker detection using graphene oxide–gold nanostructures

In this paper, a most sensitive electrochemical biosensor for detection of prostate‐specific antigen (PSA) was designed. To reach the goal, a sandwich type electrode composed of reduced graphene oxide/ gold nanoparticles (GO/AuNPs), Anti‐Total PSA monoclonal antibody, and anti‐Free PSA antibody was assembled. The functionalized materials were thoroughly characterized by atomic force microscope spectroscopy, transmission electron microscopy, and X‐ray diffraction techniques. The electrochemical properties of each of the modification step were evaluated by cyclic voltammetry and electrochemical impedance spectroscopy. The results presented that the proposed biosensor possesses high sensitivity toward total and free PSA. Furthermore, the fabricated biosensor revealed an excellent selectivity for PSA in comparison to the other tumor markers such as BHCG, Alb, CEA, CA125, and CA19‐9. The limit of detection for the proposed electrochemical biosensor was estimated to be around 0.2 and 0.07 ng/mL for total and free PSA antigen, respectively.     

Mutations in FIE, a WD polycomb group gene, allow endosperm development without fertilization

A fundamental problem in biology is to understand how fertilization initiates reproductive development. Higher plant reproduction is unique because two fertilization events are required for sexual reproduction. First, a sperm must fuse with the egg to form an embryo. A second sperm must then fuse with the adjacent central cell nucleus that replicates to form an endosperm, which is the support tissue required for embryo and/or seedling development. Here, we report cloning of the Arabidopsis FERTILIZATION-INDEPENDENT ENDOSPERM (FIE) gene. The FIE protein is a homolog of the WD motif-containing Polycomb proteins from Drosophila and mammals. These proteins function as repressors of homeotic genes. A female gametophyte with a loss-of-function allele of fie undergoes replication of the central cell nucleus and initiates endosperm development without fertilization. These results suggest that the FIE Polycomb protein functions to suppress a critical aspect of early plant reproduction, namely, endosperm development, until fertilization occurs.     

Recognition of functional genetic polymorphism using ESE motif definition: a conservative evolutionary approach to CYP2D6/CYP2C19 gene variants

Genetica - Although predicting the effects of variants near intron-exon boundaries is relatively straightforward, predicting the functional Exon Splicing Enhancers (ESEs) and the possible effects...     

Invasive aspergillosis promotes tumor growth and severity in a tumor-bearing mouse model

Invasive aspergillosis increases in chronic immunosuppressive diseases such as cancer. There is little information about the mechanisms by which Aspergillus infection affects the immune regulation and microenvironment of cancer cells. Hence, this study was aimed at investigating the effect of invasive aspergillosis on immunosurveillance, metastasis, and prognosis of cancer in tumor-bearing mice. After implantation of mouse mammary tumor in BALB/c mice, they were infected with Aspergillus conidia intravenously. For comparison, groups of mice were experimentally infected with Aspergillus conidia or implanted with tumor cells separately. Seven days after Aspergillus infection, the serum levels of tissue inhibitor of metalloproteinase-1 (TIMP-1) were measured by ELISA, and subsequently regulatory T lymphocytes were analyzed by flow cytometry. The survival of animals and mean tumor size were then determined. Our results indicated that tumor sizes in mice increased significantly after infection with Aspergillus conidia. Moreover, invasive aspergillosis enhanced the population of regulatory lymphocytes and level of TIMP-1. This study supports the idea that massive Aspergillus infection could stimulate tumor growth and increases the possibility of a bad prognosis. As a result, treatment of Aspergillus infection could be considered an important issue for efficient cancer therapy.