FEBS Letters

Collagen Human type II collagen Cartilage Hybridization mRNA Cell‐free translation

Human sapovirus (SaV) is uncultivable, but expression of the recombinant capsid protein (rVP1) in insect cells results in the formation of virus‐like particles (VLPs) that are morphologically similar to the native viruses. However, the SaV rVP1 expression levels are considerably low. We have found that inclusions of short foreign nucleotide sequences inserted directly upstream from the predicted rVP1 AUG start codon lead to increased yield of VLPs. This method allowed us to express a SaV rVP1, which could not have been expressed to measurable or practical levels otherwise.

One of the main objectives in the analysis of microarray experiments is the identification of genes that are differentially expressed under two experimental conditions. This task is complicated by the noisiness of the data and the large number of genes that are examined simultaneously. Here, we present a novel technique for identifying differentially expressed genes that does not originate from a sophisticated statistical model but rather from an analysis of biological reasoning. The new technique, which is based on calculating rank products (RP) from replicate experiments, is fast and simple. At the same time, it provides a straightforward and statistically stringent way to determine the significance level for each gene and allows for the flexible control of the false‐detection rate and familywise error rate in the multiple testing situation of a microarray experiment. We use the RP technique on three biological data sets and show that in each case it performs more reliably and consistently than the non‐parametric t‐test variant implemented in Tusher et al.'s significance analysis of microarrays (SAM). We also show that the RP results are reliable in highly noisy data. An analysis of the physiological function of the identified genes indicates that the RP approach is powerful for identifying biologically relevant expression changes. In addition, using RP can lead to a sharp reduction in the number of replicate experiments needed to obtain reproducible results.

In this review we describe the history of the development of the raft concept for membrane sub‐compartmentalization. From its early beginnings as a mechanism for apical sorting in epithelial cells the concept has evolved to a general principle for membrane organisation. After a shaky start with crude methodology based on detergent extraction the field has become increasingly sophisticated, employing a host of different methods that support the existence of dynamic raft domains in membranes. These are composed of fluctuating nanoscale assemblies of sphingolipid, cholesterol and proteins that can be stabilized to coalesce, forming platforms that function in membrane signalling and trafficking.

Các mối liên kết huỳnh quang có thể chuyển đổi quang là những thành phần chính của các kỹ thuật kính hiển vi huỳnh quang siêu phân giải mới phát triển, cho phép điều tra các hệ sinh học với độ phân giải 50 nm hoặc tốt hơn. Ngược lại với hầu hết các kỹ thuật hình ảnh huỳnh quang truyền thống, hiệu suất đạt được bởi hầu hết các kỹ thuật siêu phân giải bị ảnh hưởng đáng kể bởi tính chất chuyển đổi quang của các fluorophore. Ở đây, chúng tôi xem xét các fluorophore có thể chuyển đổi quang cho hình ảnh siêu phân giải với nội dung thảo luận về các nguyên tắc cơ bản liên quan, tập trung vào việc thực hiện thực tiễn với các công cụ có sẵn và cái nhìn về các hướng đi trong tương lai.

We have investigated immunoproteasomes in human fibroblasts during replicative senescence. Unlike levels of constitutive proteasome catalytic subunits and 26S proteasome regulatory subunits, levels of immunosubunits did not decrease dramatically in senescent cells. However, the induction of immunosubunits by interferon‐γ (IFN‐γ) was lost in senescent cells. In contrast, levels of the 11S proteasome regulator, PA28, were increased by IFN‐γ even in senescent cells, and both immunosubunits and PA28 increased with the reversible growth arrest in confluent cell cultures. The results highlight differences in the mechanisms of regulation of immunoproteasomes compared to constitutive proteasomes and in the irreversible growth arrest of senescent cells compared to reversible contact‐induced growth arrest.

Tyrosine‐rich acidic matrix protein (TRAMP; 22 kDa extracellular matrix protein; dermatopontin) is a protein that co‐purifies with lysyl oxidase and with dermatan sulphate proteoglycans, with possible functions in cell—matrix interactions and matrix assembly. Using a rabbit polyclonal antiserum raised against porcine TRAMP, which cross‐reacts with both the human and murine forms of the protein, we show by immunoblotting that TRAMP has a widespread tissue distribution, including skin, skeletal muscle, heart, lung, kidney, cartilage and bone. In cultures of human skin fibroblasts, TRAMP incorporates both [³⁵S]sulphate and [³H]tyrosine and is secreted into the medium, as shown by immunoprecipitation. Amino acid analysis of immunoprecipitated TRAMP demonstrates that many of the tyrosine residues in TRAMP are sulphated.

Photon correlation spectroscopy demonstrated for the first time that co‐purified meningococcal TbpA+B form a complex in solution. This structure bound hTf and the resultant species underwent partial dissociation after exposure to additional hTf or following prolonged incubation. Purified TbpA and TbpB had similar apparent sizes but showed distinctive size profiles suggesting that TbpA forms a largely homogeneous population while TbpB may produce more variable particle sizes under these conditions.

Cytochrome oxidase Escherichia coli Cytochrome b‐d complex Bacterial electron transport Low‐temperature technique

MicroRNAs (miRNAs) are a recently discovered family of 18–24 nucleotide non‐coding RNAs that can negatively regulate target mRNAs. All studied multicellular eukaryotes utilize miRNAs to regulate basic cellular functions including proliferation, differentiation, and death. It is now apparent that abnormal miRNA expression is a common feature of human malignancies. This review discusses the various cancer‐relevant miRNAs (oncomirs) especially in cervical tumorigenesis and the potential role of oncomirs as therapeutic agents and targets for the treatment of cervical cancer.