Life Sciences Commons^™

Biomimetic Actuators: Where Technology And Cell Biology Merge [Review Article], Michael Knoblauch, Winfried Peters

Winfried S. Peters

Photo- And Electropatterning Of Hydrogel-Encapsulated Living Cell Arrays, Dirk Albrecht, Valerie Tsang, Robert Sah, Sangeeta Bhatia

Dirk R. Albrecht

Living cells have the potential to serve as sensors, naturally integrating the response to stimuli to generate predictions about cell fate (e.g., differentiation, migration, proliferation, apoptosis). Miniaturized arrays of living cells further offer the capability to interrogate many cells in parallel and thereby enable high-throughput and/or combinatorial assays. However, the interface between living cells and synthetic chip platforms is a critical one wherein the cellular phenotype must be preserved to generate useful signals. While some cell types retain tissue-specific features on a flat (2-D) surface, it has become increasingly apparent that a 3-D physical environment will be required for others. …

Embryonic Expression Of Pre-Initiation Dna Replication Factors In Xenopus Laevis, Brian Walter, Jonathan Henry

Brian Walter

We examined the expression of various DNA replication factors, including: cdc45, the factors of the GINS heterotetramer (Sld5, Psf1, Psf2, Psf3), and PCNA, in Xenopus laevis during embryonic development via whole mount in situ hybridization. For the most part, these factors were expressed in similar patterns, with some subtle variations, throughout development within the anterior CNS, pharyngeal arches, and various placodes. More significant variations were also observed, including expression of only Psf1 and Psf2 in the pronephros and unique Psf2 expression in the somitic mesoderm. Overall, these results suggest that common regulatory mechanisms are involved in the transcriptional deployment of …

Forisomes, A Novel Type Of Ca2+-Dependent Contractile Protein Motor [Review Article], Michael Knoblauch, Winfried Peters

Winfried S. Peters

Molecular Profiling: Gene Expression Reveals Discrete Phases Of Lens Induction And Development In Xenopus Laevis, Brian Walter, Yimin Tian, Amy Garlisch, Maria Carinato, Matthew Elkins, Adam Wolfe, Jonathan Schaefer, Kimberly Perry, Jonathan Henry

Brian Walter

No abstract provided.

A Long Drink Of Water: How Xylem Changes With Depth, Gretchen North

Gretchen North

No abstract provided.

Aquaporins Account For Variations In Hydraulic Conductance For Metabolically Active Root Regions Of Agave Deserti In Wet, Dry, And Rewetted Soil, Gretchen North, P. Martre, P. Nobel

Gretchen North

The importance of aquaporins for root hydraulic conductance (LP) was investigated along roots of the desert succulent Agave deserti in wet, dry and rewetted soil. Water channel activity was inferred from HgCl2-induced reductions of LP that were reversible by 2-mercaptoethanol. Under wet conditions, HgCl2 reduced LP for the distal root region by 50% and for the root region near the shoot base by 36% but did not affect LP for the mid-root region. For all root regions, LP decreased by 30–60% during 10 d in drying soil and was not further reduced by HgCl2. After soil rewetting, LP increased to …

Species Specificity In Pollen-Pistil Interactions, Rob Swanson

Rob Swanson

For pollination to succeed, pollen must carry sperm through a variety of different floral tissues to access the ovules within the pistil. The pistil provides everything the pollen requires for success in this endeavor including distinct guidance cues and essential nutrients that allow the pollen tube to traverse enormous distances along a complex path to the unfertilized ovule. Although the pistil is a great facilitator of pollen function, it can also be viewed as an elaborate barrier that shields ovules from access from inappropriate pollen, such as pollen from other species. Each discrete step taken by pollen tubes en route …

Pollen And Stigma Structure And Function: The Role Of Diversity In Pollination, Rob Swanson

Rob Swanson

The ornate surfaces of male and female reproductive cells in flowering plants have long attracted attention for their variety and evolutionary significance. These structures, and the molecules involved in sexual interactions, remain among the most rapidly evolving and diverse characteristics known. As varied as they may be, each element takes part in performing the same functions, protecting pollen and stigma from the environment, delivering and capturing pollen, promoting pollen hydration and germination, allowing the entry of appropriate pollen tubes into the stigma, and guiding the tubes to the ovary (Figure 1 A). In this review, we (1) survey recent discoveries …