Vision and change in the biology community: snapshots of change.

Six years after the initial Vision and Change conversations, it is important to try to determine the extent of dissemination and implementation of the initiative. There is good evidence of use by some segments of the biology community; however, there is less use of Vision and Change principles or even acknowledgment of its existence within other segments.

On the edge of mathematics and biology integration: improving quantitative skills in undergraduate biology education.

The feature describes two major efforts to integrate mathematics and biology. A call is made to biologists to consider the need to address biology undergraduate education changes and to use the resources described.

Chromatin structure as a mediator of aging.

The aging process is characterized by gradual changes to an organism's macromolecules, which negatively impacts biological processes. The complex macromolecular structure of chromatin regulates all nuclear processes requiring access to the DNA sequence. As such, maintenance of chromatin structure is an integral component to deter premature aging.

Elevated histone expression promotes life span extension.

Changes to the chromatin structure accompany aging, but the molecular mechanisms underlying aging and the accompanying changes to the chromatin are unclear. Here, we report a mechanism whereby altering chromatin structure regulates life span. We show that normal aging is accompanied by a profound loss of histone proteins from the genome.

Acetylated lysine 56 on histone H3 drives chromatin assembly after repair and signals for the completion of repair.

DNA damage causes checkpoint activation leading to cell cycle arrest and repair, during which the chromatin structure is disrupted. The mechanisms whereby chromatin structure and cell cycle progression are restored after DNA repair are largely unknown. We show that chromatin reassembly following double-strand break (DSB) repair requires the histone chaperone Asf1 and that absence of Asf1 causes cell death, as cells are unable to recover from the DNA damage checkpoint.

Role of the C terminus of the ribonucleotide reductase large subunit in enzyme regeneration and its inhibition by Sml1.

Ribonucleotide reductase maintains cellular deoxyribonucleotide pools and is thus tightly regulated during the cell cycle to ensure high fidelity in DNA replication. The Sml1 protein inhibits ribonucleotide reductase activity by binding to the R1 subunit. At the completion of each turnover cycle, the active site of R1 becomes oxidized and subsequently regenerated by a cysteine pair (CX2C) at its C-terminal domain (R1-CTD).

Combinatorial materials research applied to the development of new surface coatings I: a multiwell plate screening method for the high-throughput assessment of bacterial biofilm retention on surfaces.

Combinatorial, high-throughput capabilities have been established to aid in the rapid development of new and effective antifouling marine coatings for naval applications. A biological screening process involving marine bacteria was developed that allows for rapid and effective quantification of bacterial biofilm growth and retention on large numbers of coating surfaces in parallel. The screening process involves (1) multiwell plate modifications for coating deposition, (2) deposition of combinatorial coating libraries via an automated liquid dispensing robot, (3) coating thickness measurements of cured coatings, (4) preconditioning of coatings via immersion in deionized water, (5) bacterial incubation, (6) plate processing, and (7) data analysis for identification of promising candidates.