C. elegans spermatogenesis employs lysosome-related fibrous body-membranous organelles (FB-MOs) for transport of many cellular components. Previous work showed that spe-10 mutants contain FB-MOs that prematurely disassemble, resulting in defective transport of FB components into developing spermatids. Consequently, spe-10 spermatids are smaller than wild type and contain defective FB-MO derivatives. In this article, we show that spe-10 encodes a four-pass integral membrane protein that has a DHHC-CRD zinc-finger motif. The DHHC-CRD motif is found in a large, diverse family of proteins that have been implicated in palmitoyl transfer during protein lipidation. Seven spe-10 mutants were analyzed, including missense, nonsense, and deletion mutants. An antiserum to SPE-10 showed significant colocalization with a known marker for the FB-MOs during wild-type spermatogenesis. In contrast, the spe-10(ok1149) deletion mutant lacked detectable SPE-10 staining; this mutant lacks a spe-10 promoter and most coding sequence. The spe-10(eb64) missense mutation, which changes a conserved residue within the DHHC-CRD domain in all homologues, behaves as a null mutant. These results suggest that wild-type SPE-10 is required for the MO to properly deliver the FB to the C. elegans spermatid and the DHHC-CRD domain is essential for this function.

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The isolation of pure nucleic acids from clinical samples is a crucial step in the molecular diagnosis of viral infections by nucleic acid testing (NAT). In this study, novel flat glass devices (cards) were demonstrated to support the rapid and efficient extraction of nucleic acids from upper respiratory tract specimens (nasal washes and swabs). The performance of the nucleic acid extraction cards was directly compared to an existing standardized and automated platform for viral extraction from these types of specimens. The flowthrough card method improved the speed of nucleic acid purification and accommodated larger sample volumes in extraction of bacteriophage MS2 RNA from the various specimen matrices. The dynamic range and estimated sensitivity of the card extraction method for reverse transcriptase quantitative real-time PCR (RT-qPCR)-based detection approximate those of the standardized magnetic glass bead extraction method used in this study.Molecular diagnostic tests are widely used in clinical virology to detect a range of respiratory tract viral infections. Methods for nucleic acid (NA) extraction of upper respiratory tract samples have recently been standardized with the availability of FDA-510(k)-approved tests for respiratory viruses such as the Nanosphere Verigene SP respiratory virus nucleic acid test and the Prodesse ProFlu, Luminex RVP xTAG, and CDC multiplex flu tests. Approved extraction methods for these highly complex tests (with the exception of the moderately complex Nanosphere test) are slow, and they tend to process lower clinical sample volumes than do other tests. The NucliSens EasyMag extraction system (bioMérieux, Marcy l'Etoile, France) has been compared to the BioRobot 9604 (Qiagen GmbH, Hilden, Germany) and to the manual QIAamp RNA/DNA extraction kit (Qiagen GmbH) for the detection of NAs from viral respiratory tract pathogens using reverse transcriptase quantitative real-time PCR (RT-qPCR) assays (7). The performances of these systems for extracting (0.14-to 0.25-ml) volumes of respiratory tract samples were shown to be equivalent, but the advantages of the automated systems were speed and better cross-contamination control, whereas the manual method was less expensive but required more manipulation than did the automated systems.Extraction kits and systems commonly used to extract respiratory tract samples (7) often use finely divided glass particles or magnetic glass beads as the nucleic acid binding matrix and chaotropic salt binding and wash buffers (4, 5). These silica particles offer a greater surface area for binding of NAs (18,19), but the porous matrix can release trapped contaminants that may be inhibitory to NA testing (NAT) or even sequester target NAs (14,19). In addition, these types of columns do not bind small DNA molecules (up to about 150 bp) efficiently (9, 16; M. W. Reed et al., U.S. patent application 12/348,244).We have previously demonstrated that glass microscope slides could be used to purify genomic DNA from various sample types in an open system (12), ...