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Hers And His: Silk Glands Used In Egg Sac Construction By Female Spiders Potentially Repurposed By A 'Modern' Male Spider, Mark A. Townley, Danilo Harms

Biological Sciences

Cylindrical silk gland (CY) spigots distinguish a large clade of modern spiders, the CY spigot clade, which includes all entelegyne spiders and their closest relatives. Following a widespread paradigm, CYs and their spigots are only known to occur in female spiders and they produce silk used in the construction of egg sacs. Here we report the occurrence of a CY spigot or CY nubbin on each posterior median spinneret (PMS) in males (5th stadium and later) of the spider Australomimetus maculosus. Late juvenile males had a CY spigot on each PMS, whereas adult males either had a CY spigot or, …

From Spinning Silk To Spreading Saliva: Mouthpart Remodeling In Manduca Sexta (Lepidoptera: Sphingidae), Istvan Miko, Sarthok Rasique Rahman, Anne C. Jones, Mark A. Townley, Brandon Gominho, Sulav Paudel, S David Stupski, Heather M. Hines, Rudolf J. Schilder

Biological Sciences

As a model organism, the tobacco hornworm Manduca sexta (Linnaeus 1763) has contributed much to our knowledge of developmental processes in insects, and major developmental changes between different larval instars are generally well understood. Second and later instars of M. sexta do not produce silk, and their spinneret and accessory labial glands (=Lyonet’s glands), structures thought to be key players in silk production in other lepidopterans, are highly reduced. To our knowledge, mouthparts and labial gland morphology of the silk-producing first instar have never been described. In this study, we compared the mouthpart morphology and transcriptome profile of first and …

Estimating Plasma Volume In Neonatal Holstein Calves Fed One Or Two Feedings Of A Lacteal-Based Colostrum Replacer Using Evans Blue Dye And Hematocrit Values At Various Time Points., Peter S. Erickson, Rosemarie G. Cabral Ph.D., Colleen E. Chapman Ms, E. J. Kent

Biological Sciences

Twenty-eight Holstein calves were blocked by birth date and randomly assigned to one of two treatments to investigate the effect of colostrum replacer (CR) feeding regimen on plasma volume (PV). Treatments were: 1) one feeding of CR (C₁; 3L of reconstituted CR 675 g of powder providing 184.5 g of IgG at birth) or 2) two feedings of CR (C₂; 2L of reconstituted CR at birth and 1 L of reconstituted CR at six h). By 6 h of age, all calves had received 3L of CR providing 184.5 g …

Conservation And Loss Of Ribosomal Rna Gene Sites In Diploid And Polyploid Fragaria (Rosaceae), Bo Liu, Thomas M. Davis

Biological Sciences

The genus Fragaria comprises species at ploidy levels ranging from diploid (2n = 2x = 14) to decaploid (2n = 10x = 70). Fluorescence in situ hybridization with 5S and 25S rDNA probes was performed to gather cytogenetic information that illuminates genomic divergence among different taxa at multiple ploidy levels, as well as to explore the evolution of ribosomal RNA genes during polyploidization in Fragaria.

A Strawberry Knox Gene Regulates Leaf, Flower And Meristem Architecture, Mithu Chatterjee, Claudia L. Bermudez-Lozano, Maureen A. Clancy, Thomas M. Davis, Kevin M. Folta

Biological Sciences

The KNOTTED-LIKE HOMEODOMAIN (KNOX) genes play a central role in maintenance of the shoot apical meristem. They also contribute to the morphology of simple and compound leaves. In this report we characterize the FaKNOX1 gene from strawberry (Fragaria spp.) and demonstrate its function in trasgenic plants. The FaKNOX1 cDNA was isolated from a cultivated strawberry (F.×ananassa) flower EST library. The sequence is most similar to Class I KNOX genes, and was mapped to linkage group VI of the diploid strawberry genome. Unlike most KNOX genes studied, steady-state transcript levels were highest in flowers and fruits. Transcripts were also detected in …

An Examination Of Targeted Gene Neighborhoods In Strawberry, Thomas M. Davis, Melanie E. Shields, Qian Zhang, Denise Tombolato-Terzić, Jeffrey L. Bennetzen, Ana C. Pontaroli, Hao Wang, Qin Yao, Phillip Sanmiguel, Kevin M. Folta

Biological Sciences

This report details the structure and content of targeted regions of the strawberry genome. The data indicate that the strawberry genome is gene-dense, with an average of one protein-encoding gene or pseudogene per 5.9 kb. Current overall EST coverage is sparse. The unexpected gene duplications and their differential patterns of EST support suggest possible subfunctionalization or pseudogenization of these sequences. This report provides a high-resolution depiction of targeted gene neighborhoods that will aid whole-genome sequence assembly, provide valuable tools for plant breeders and advance the understanding of strawberry genome evolution.

The Loss Of Species: Mangrove Extinction Risk And Geographic Areas Of Global Concern, Beth A. Liu, Kent A. Carpenter, Lorna Collins, Norma C. Duke, Aaron M. Ellison, Joanne C. Ellison, Elizabeth J. Farnsworth, Edwino S. Fernando, Kandasamy Kathiresan, Nico E. Koedam, Suzanne R. Livingstone, Toyohiko Miyagi, Gregg E. Moore, Vien Ngoc Nam, Jin Eong Ong, Jurgenne H. Primavera, Severino G. Salmo Iii, Jonnell C. Sanciangco, Sukristijono Sukardjo, Yamin Wang, Jean Wan Hong Yong

Biological Sciences

Mangrove species are uniquely adapted to tropical and subtropical coasts, and although relatively low in number of species, mangrove forests provide at least US $1.6 billion each year in ecosystem services and support coastal livelihoods worldwide. Globally, mangrove areas are declining rapidly as they are cleared for coastal development and aquaculture and logged for timber and fuel production. Little is known about the effects of mangrove area loss on individual mangrove species and local or regional populations. To address this gap, species-specific information on global distribution, population status, life history traits, and major threats were compiled for each of the …

An Enhanced Method For Sequence Walking And Paralog Mining: Topo® Vector-Ligation Pcr, Benjamin B. Orcheski, Thomas M. Davis

Biological Sciences

Background

Although technological advances allow for the economical acquisition of whole genome sequences, many organisms' genomes remain unsequenced, and fully sequenced genomes may contain gaps. Researchers reliant upon partial genomic or heterologous sequence information require methods for obtaining unknown sequences from loci of interest. Various PCR based techniques are available for sequence walking - i.e., the acquisition of unknown DNA sequence adjacent to known sequence. Many such methods require rigid, elaborate protocols and/or impose narrowly confined options in the choice of restriction enzymes for necessary genomic digests. We describe a new method, TOPO^® Vector-Ligation PCR (or TVL-PCR) that innovatively …

Effects Of A Large Fishing Closure On Benthic Communities In The Western Gulf Of Maine: Recovery From The Effects Of Gillnets And Otter Trawls, Raymond E. Grizzle, Larry G. Ward, Larry A. Mayer, Mashkoor A. Malik, Andrew B. Cooper, Holly A. Abeels, Jennifer K. Greene, Melissa A. Brodeur, Andrew A. Rosenberg

Biological Sciences

The recovery of benthic communities inside the western Gulf of Maine fishing closure area was evaluated by comparing invertebrate assemblages at sites inside and outside of the closure four to six years after the closure was established. The major restriction imposed by the closure was a year-round prohibition of bottom gillnets and otter trawls. A total of 163 seafloor sites (similar to half inside and half outside the closure) within a 515-km(2) study area were sampled with some combination of Shipek grab, Wildco box corer, or underwater video. Bottom types ranged from mud (silt and clay) to boulders, and the …

Age And Growth Estimates Of The Thorny Skate (Amblyraja Radiata) In The Western Gulf Of Maine, James A. Sulikowski, Jeff Kneebone, Scott Elzey, Joe Jurek, Patrick D. Danley, William Huntting Howell, Paul C.W. Tsang

Biological Sciences

The northwest Atlantic population of thorny skates (Amblyraja radiata) inhabits an area that ranges from Greenland and Hudson Bay, Canada, to South Carolina. Despite such a wide range, very little is known about most aspects of the biology of this species. Recent stock assessment studies in the northeast United States indicate that the biomass of the thorny skate is below the threshold levels mandated by the Sustainable Fisheries Act. In order to gain insight into the life history of this skate, we estimated age and growth for thorny skates, using vertebral band counts from 224 individuals ranging in size from …

The Reproductive Cycle Of The Thorny Skate (Amblyraid Radiata) In The Western Gulf Of Maine, James A. Sulikowski, Jeff Kneebone, Scott Elzey, Joe Jurek, Patrick D. Danley, William Huntting Howell, Paul C.W. Tsang

Biological Sciences

The thorny skate (Amblyraja radiata) is a large species of skate that is endemic to the waters of the western north Atlantic in the Gulf of Maine. Because the biomass of thorny skates has recently declined below threshold levels mandated by the Sustainable Fisheries Act, commercial harvests from this region are prohibited. We have undertaken a comprehensive study to gain insight into the life history of this skate. The present study describes and characterizes the reproductive cycle of female and male thorny skates, based on monthly samples taken off the coast of New Hampshire, from May 2001 to May 2003. …

Age And Growth Estimates Of The Winter Skate (Leucoraja Ocellata) In The Western Gulf Of Maine, James A. Sulikowski, Michael D. Morin, Seung H. Suk, William Huntting Howell

Biological Sciences

The northwest Atlantic population of thorny skates (Amblyraja radiata) inhabits an area that ranges from Greenland and Hudson Bay, Canada, to South Carolina. Despite such a wide range, very little is known about most aspects of the biology of this species. Recent stock assessment studies in the northeast United States indicate that the biomass of the thorny skate is below the threshold levels mandated by the Sustainable Fisheries Act. In order to gain insight into the life history of this skate, we estimated age and growth for thorny skates, using vertebral band counts from 224 individuals ranging in size from …

Plasma And Testicular Testosterone Levels, Volume Density And Number Of Leydig Cells And Spermatogenic Efficiency Of Rabbits, A.C.S. Castro, William E. Berndtson, F. M. Cardoso

Biological Sciences

Plasma and tissue testosterone concentrations were determined by radioimmunoassay in 12 eight-month-old sexually mature New Zealand White rabbits and evaluated for possible associations with spermatogenic efficiency as well as with volume density and number of Leydig cells. Testicular tissue was processed histologically and histometry was performed in order to quantify germ cells, Sertoli cells and Leydig cells. Spermatogenic efficiency, reported as the ratios among germ cells (spermatogonia, primary spermatocytes and round spermatids) and by the ratio of germ cells to Sertoli cells, was not associated with testosterone levels. However, Leydig cell parameters such as number of Leydig cells per gram …