Factors associated with accuracy in sampling fish eggs and larvae

Ichthyoplankton sampling gear is reviewed and evaluated with emphasis on power plant impact assessment. Effects of biotic and abiotic factors on gear accuracy are discussed. Difficulties associated with obtaining representative samples from patchy population distributions are acknowledged. A listing of commonly used sampling gear has been compiled and indexed by ecosystem. Meter nets and variations of meter nets are the most widely used gear for sampling fish eggs and larvae. Comparative gear evaluation has been performed based on information compiled in the report. Although the diversity of habitats and the great number of relatively important species makes summarization difficult, the following comparisons are made. Meter nets sample greater length interval s and greater numbers of fish larvae per unit volume than half meter nets. Bridleless Bongo nets are more efficient in sampling larger larvae than meter nets . High volume pumps sample fewer or equal numbers of fish eggs than half meter and meter nets, but may provide better estimates of larger larvae. A check list highlighting important factors to consider when selecting gear is provided. Features to be optimized in gear design and deployment are summarized

Ecological study of the tidal segment of the James River encompassing Hog Point : 1975 final technical report

Volume 1: Technical Reports Section 1: River Biota and Phytoplankton Entrainment Studies at the VEPCO Surry Nuclear Power Station Section 2: Zooplankton Entrainment at the Surry Nuclear Power Plant, James River, Virginia by G. C. Grant and B. B. Bryan Section 3: a. Plant Entrainment of Ichthyoplankton at the VEPCO Nuclear Power Station by J. V. Merriner and A. D. Estes b: Thermal Plume Entrainment of Ichthyoplankton at the· VEPCO Nuclear Power Station by J. V. Merriner and A. D. Este

A novel protein, sperm head and tail associated protein (SHTAP), interacts with cysteine-rich secretory protein 2 (CRISP2) during spermatogenesis in the mouse

CRISP2 (cysteine-rich secretory protein 2) is a sperm acrosome and tail protein with the ability to regulate Ca2+ flow through ryanodine receptors. Based on these properties, CRISP2 has a potential role in fertilization through the regulation of ion signalling in the acrosome reaction and sperm motility. The purpose of the present study was to determine the expression, subcellular localization and the role in spermatogenesis of a novel CRISP2-binding partner, which we have designated SHTAP (sperm head and tail associated protein).Using yeast two-hybrid screens of an adult testis expression library, we identified SHTAP as a novel mouse CRISP2-binding partner. Sequence analysis of all Shtap cDNA clones revealed that the mouse Shtap gene is embedded within a gene encoding the unrelated protein NSUN4 (NOL1/NOP2/Sun domain family member 4). Five orthologues of the Shtap gene have been annotated in public databases. SHTAP and its orthologues showed no significant sequence similarity to any known protein or functional motifs, including NSUN4. Using an SHTAP antiserum, multiple SHTAP isoforms (approximately 20-87 kDa) were detected in the testis, sperm, and various somatic tissues. Interestingly, only the approximately 26 kDa isoform of SHTAP was able to interact with CRISP2. Furthermore, yeast two-hybrid assays showed that both the CAP (CRISP/antigen 5/pathogenesis related-1) and CRISP domains of CRISP2 were required for maximal binding to SHTAP. SHTAP protein was localized to the peri-acrosomal region of round spermatids, and the head and tail of the elongated spermatids and sperm tail where it co-localized with CRISP2. During sperm capacitation, SHTAP and the SHTAP-CRISP2 complex appeared to be redistributed within the head.The present study is the first report of the identification, annotation and expression analysis of the mouse Shtap gene. The redistribution observed during sperm capacitation raises the possibility that SHTAP and the SHTAP-CRISP2 complex play a role in the attainment of sperm functional competence.Duangporn Jamsai, Sewa Rijal, Deborah M. Bianco, Anne E. O'Connor, Donna J. Merriner ... Moira K. O'Bryan ... et al

Annulus and mitochondrial disruption in SLIRP KO sperm.

<p>Electron micrographs of the distal mid-piece and annulus region of (A) WT and (B) SLIRP KO sperm. White arrows, annulus; white bar, abnormal mid-piece/annulus junction in KO sperm; black arrows, electron light and dense areas in WT and KO mitochondria respectively. Black bars, 0.5 µm.</p