Over‐expression of MSG1 Transcriptional Co‐activator Increases Melanin in B16 Melanoma Cells: A Possible Role for MSG1 in Melanogenesis

MSG1 is a 27 kDa nuclear protein that is expressed strongly in melanotic B16 melanoma cells but very weakly in amelanotic B16 cells. Transient expression of B16 cells with an expression vector for MSG1 resulted in an increase in levels of the enzyme dopachrome tautomerase but not tyrosinase, as detected by western blotting. Stable transfection of B16 melanoma cells with plasmids containing the full length MSG1 or its deletion mutants, however, generated cell lines that showed an increase in levels of tyrosinase, dopachrome tautomerase and cellular melanin when compared with control transfected cells. Our results suggest that MSG1 plays an important role in melanogenesis, by regulating the levels of the enzymes of the pigmentary system via tyrosinase and dopachrome tautomerase.     

Expression vectors for chicken–human chimeric antibodies

The chicken is a useful animal for preparation of antibodies that are reactive with highly conserved mammalian molecules. For further clinical application of chicken antibodies, we constructed the novel expression vectors for chicken–human chimeric antibodies, pcSLCγ1, pcSLCγ4 and pcSLCκ. These vectors had the following characteristics: (1) any chicken variable regions from hybridomas or a phage display library can be easily introduced; (2) the variable regions are able to be expressed in different immunoglobulin isotypes; and (3) the chimeric antibodies can be highly expressed in either transiently or stably transfected eukaryotic cells (COS-7 and CHO-K1 cells). Western blot analysis of the chimeric antibodies revealed that the expressed products were of the predicted size, structure and specificity. These results indicate that these vectors are useful tools for the chimerization of chicken antibodies.     

Integrating information literacy training into an inquiry-based introductory biology laboratory

ABSTRACT

Information literacy is an essential skill for biologists; however, most biology curricula do not intentionally integrate information literacy into classroom and laboratory exercises. There is evidence that developing information literacy skills in undergraduates improves their research skills, writing, and GPAs. Our objective was to integrate information literacy skills into a first semester introductory biology laboratory with a multi-week, inquiry-based module that leverages primary literature. Here we describe the module, which challenges students to develop and test a hypothesis related to parental care behaviour in birds. Students form hypotheses based on literature searching done during librarian-led information literacy sessions, produce an annotated bibliography, collect and analyse video data of barn swallows feeding their offspring, and present their findings. Analysis of students’ annotated bibliographies indicates that 83% of the referenced papers were appropriate for developing their specific hypotheses. The key elements ofa successful information literacy training plan include faculty-librarian collaboration, multiple classroom or laboratory sessions that introduce or utilize information literacy, and relevance ofthe information literacy training to an assignment. By introducing information literacy early inbiology curricula, departments can develop tiered information literacy plans that incorporate opportunities for students to use and refine these skills throughout their studies.     

Vulnerability of a large monomictic lake (Lake Biwa) to warm winter event

Detailed cross-sectional temperature and oxygen distributions during winter were examined over 5 years (2003–2007) in large, warm, monomictic Lake Biwa. The distribution patterns showed year-to-year variation in the degree of spatial heterogeneity and indicated that both convective mixing and gravity currents contributed to the delivery of oxygen to the profundal zone. We encountered a warm winter in 2007, when deep-water oxygenation was delayed by more than a month relative to normal years. Data obtained during the period of oxygenation in 2007 suggest that the timing of complete oxygenation of the bottom water (or lower layers of the hypolimnion) was controlled by physical processes responsible for destruction of the weak thermal stratification near the bottom. This study revealed that Lake Biwa is sensitive to year-to-year variations in winter meteorological conditions. Specifically, the bottom environments are highly susceptible to a warm winter, especially when it follows a cold winter.