Life Sciences Commons^™

Regulation Of Kv11.1 Potassium Channel C-Terminal Isoform Expression By The Rna-Binding Proteins Hur And Hud, Qiuming Gong, Matthew R. Stump, Zhengfeng Zhou

Faculty Publications - Department of Biological & Molecular Science

The potassium voltage-gated channel subfamily H member 2 (KCNH2) gene encodes the Kv11.1 potassium channel, which conducts the rapidly activating delayed rectifier current in the heart. KCNH2 pre-mRNA undergoes alternative polyadenylation and forms a functional, full-length Kv11.1a isoform if exon 15 is polyadenylated or a nonfunctional, C-terminally truncated Kv11.1a-USO isoform if intron 9 is polyadenylated. The molecular mechanisms that regulate Kv11.1 isoform expression are poorly understood. In this study, using HEK293 cells and reporter gene expression, pulldown assays, and RNase protection assays, we identified the RNA-binding proteins Hu antigen R (HuR) and Hu antigen D (HuD) as regulators of Kv11.1 …

Rivoli's Hummingbird: Eugenes Fulgens, Donald R. Powers

Faculty Publications - Department of Biological & Molecular Science

Rivoli's Hummingbird was named in honor of the Duke of Rivoli when the species was described by René Lesson in 1829. Even when it became known that William Swainson had written an earlier description of this species in 1827, the common name Rivoli's Hummingbird remained until the early 1980s, when it was changed to Magnificent Hummingbird. In 2017, however, the name was restored to Rivoli's Hummingbird when the American Ornithological Society officially recognized Eugenes fulgens as a distinct species from E. spectabilis, the Talamanca Hummingbird, of the highlands of Costa Rica and western Panama.

Rivoli's Hummingbird is found from the …

Integrating Morphology And Kinematics In The Scaling Of Hummingbird Hovering Metabolic Rate And Efficiency, Derrick J. E. Groom, M. Cecilia B. Toledo, Donald R. Powers, Bret W. Tobalske, Kenneth C. Welch Jr.

Faculty Publications - Department of Biological & Molecular Science

Wing kinematics and morphology are influential upon the aerodynamics of flight. However, there is a lack of studies linking these variables to metabolic costs, particularly in the context of morphological adaptation to body size. Furthermore, the conversion efficiency from chemical energy into movement by the muscles (mechanochemical efficiency) scales with mass in terrestrial quadrupeds, but this scaling relationship has not been demonstrated within flying vertebrates. Positive scaling of efficiency with body size may reduce the metabolic costs of flight for relatively larger species. Here, we assembled a dataset of morphological, kinematic, and metabolic data on hovering hummingbirds to explore the …

Upregulation Of Functional Kv11.1a Isoform Expression By Modified U1 Small Nuclear Rna, Qiuming Gong, Matthew R. Stump, Zhengfeng Zhou

Faculty Publications - Department of Biological & Molecular Science

The KCNH2 or human ether-a go-go-related gene (hERG) encodes the Kv11.1 potassium channel that conducts the rapidly activating delayed rectifier potassium current in the heart. The expression of Kv11.1 C-terminal isoforms is directed by the alternative splicing and polyadenylation of intron 9. Splicing of intron 9 leads to the formation of a functional, full-length Kv11.1a isoform and polyadenylation of intron 9 results in the production of a non-functional, C-terminally truncated Kv11.1a-USO isoform. The relative expression of Kv11.1a and Kv11.1a-USO plays an important role in regulating Kv11.1 channel function. In the heart, only one-third of KCNH2 pre-mRNA is processed to Kv11.1a …

Energetic Consequences For A Northern, Range-Edge Lizard Population, Sean D. Powers, Matthew R. Mcternan, Donald R. Powers, Roger A. Anderson

Faculty Publications - Department of Biological & Molecular Science

Lizards at the northern, cool edge of their geographic range in the northern hemisphere should encounter environmental conditions that differ from those living near the core of their range. To better understand how modest climate differences affect lizard energetics, we compared daily feeding and metabolism rates of individual Sceloporus occidentalis in two populations during mid-summer. Chuckanut Beach (CB) was a cool, maritime climate in northern Washington State, and Sondino Ranch (SR) was a warmer, drier climate in southern, inland Washington. We found no difference between populations in daily energy expenditure (DEE), as calculated from doubly labeled water estimates. The CB …

Drosophila Exo70 Is Essential For Neurite Extension And Survival Under Thermal Stress, Alex Chun Koon, Zhefan Stephan Chen, Shaohong Peng, Joyce Man See Fung, Xiaoman Zhang, Kayly M. Lembke, Hoi Kin Chow, C. Andrew Frank, Liwen Jiang, Kwok-Fai Lau, Ho Yin Edwin Chan

Faculty Publications - Department of Biological & Molecular Science

The octomeric exocyst complex governs the final step of exocytosis in both plants and animals. Its roles, however, extend beyond exocytosis and include organelle biogenesis, ciliogenesis, cell migration, and cell growth. Exo70 is a conserved component of the exocyst whose function in Drosophila is unclear. In this study, we characterized two mutant alleles of Drosophila exo70. exo70 mutants exhibit reduced synaptic growth, locomotor activity, glutamate receptor density, and mEPSP amplitude. We found that presynaptic Exo70 is necessary for normal synaptic growth at the neuromuscular junction (NMJ). At the neuromuscular junction, exo70 genetically interacts with the small GTPase ralA to regulate …