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SUMMARY Wnt5a directs the assembly of “Wnt-receptor-actin-myosin-polarity (WRAMP)” structure, which integrates cell adhesion receptors with F-actin and myosin to form a microfilament array associated with multivesicular bodies. The WRAMP structure is polarized to the cell posterior, where it directs tail-end membrane retraction, driving forward translocation of the cell body. Here, we define constituents of the WRAMP proteome, including regulators of microfilament and microtubule dynamics, protein interactions, and enzymatic activity. IQGAP1, a scaffold for F-actin nucleation and crosslinking, is necessary for WRAMP structure formation, potentially bridging microfilaments and MVBs. Vesicle coat proteins, including coatomer-I subunits, localize to and are required for the WRAMP structure. Electron microscopy and live imaging demonstrate movement of ER to the WRAMP structure and plasma membrane, followed by elevation of intracellular Ca2+. Thus, Wnt5a controls directional movement by recruiting cortical ER to mobilize a rear-directed, localized Ca2+ signal, activating actomyosin contraction and adhesion disassembly for membrane retraction.

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Two experiments are reported concerning the role of output interference on die recall of organized material. Croups of Ss received blocked presentation of a 49-item list consisting of seven items in each of seven categories. At recall, the category name served as the retrieval cue. In Experiment I, a 20-sec recall interval was allowed for each category, and in Experiment n, this interval was increased to 90 sec. The results of both studies indicated that the number of words recalled from a category is dependent on the position of the category in the output sequence. In general, the earlier a category appears in the output sequence, the greater the number of words recalled from that category.

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