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S J Farlow

Publications and source records attributed to S J Farlow.

3 recordsLinked to original sources

Novel dendritic kinesin sorting identified by different process targeting of two related kinesins: KIF21A and KIF21B.

Neurons use kinesin and dynein microtubule-dependent motor proteins to transport essential cellular components along axonal and dendritic microtubules. In a search for new kinesin-like proteins, we identified two neuronally enriched mouse kinesins that provide insight into a unique intracellular kinesin targeting mechanism in neurons. KIF21A and KIF21B share colinear amino acid similarity to each other, but not to any previously identified kinesins outside of the motor domain. Each protein also contains a domain of seven WD-40 repeats, which may be involved in binding to cargoes. Despite the amino acid sequence similarity between KIF21A and KIF21B, these proteins localize differently to dendrites and axons. KIF21A protein is localized throughout neurons, while KIF21B protein is highly enriched in dendrites. The plus end-directed motor activity of KIF21B and its enrichment in dendrites indicate that models suggesting that minus end-directed motor activity is sufficient for dendrite specific motor localization are inadequate. We suggest that a novel kinesin sorting mechanism is used by neurons to localize KIF21B protein to dendrites since its mRNA is restricted to the cell body.

Animals↗

The dynein gene family in Chlamydomonas reinhardtii.

To correlate dynein heavy chain (Dhc) genes with flagellar mutations and gain insight into the function of specific dynein isoforms, we placed eight members of the Dhc gene family on the genetic map of Chlamydomonas. Using a PCR-based strategy, we cloned 11 Dhc genes from Chlamydomonas. Comparisons with other Dhc genes indicate that two clones correspond to genes encoding the alpha and beta heavy chains of the outer dynein arm. Alignment of the predicted amino acid sequences spanning the nucleotide binding site indicates that the remaining nine clones can be subdivided into three groups that are likely to include representatives of the inner-arm Dhc isoforms. Gene-specific probes reveal that each clone represents a single-copy gene that is expressed as a transcript of the appropriate size (> 13 kb) sufficient to encode a high molecular weight Dhc polypeptide. The expression of all nine genes is upregulated in response to deflagellation, suggesting a role in axoneme assembly or motility. Restriction fragment length polymorphisms between divergent C. reinhardtii strains have been used to place each Dhc gene on the genetic map of Chlamydomonas. These studies lay the groundwork for correlating defects in different Dhc genes with specific flagellar mutations.

Amino Acid Sequence↗

Red cell antibody identification by solid phase red cell adherence utilizing dried RBC monolayers.

Recent technological advances in the immobilization and drying of red cell monolayers for use in solid phase red cell adherence (SPRCA) assays have resulted in the development of reagent red cells for antibody screening and identification that are stable at mom temperature. Panels consisting of twelve different RBC samples dried onto individual microplate wells were evaluated with 176 samples whose antibody specificities had previously been determined by conventional hemagglutination techniques. Identification tests performed with dried SPRCA panels proved to be more sensitive and less time consuming than hemagglutination tests. The red cell antigens of dried membranes were shown to be stable and reactive following storage for 120 days at mom temperature.

Journal Article↗