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The power system structure of a hybrid electric vehicle (HEV) critically affects the performance of the vehicle. This study presents a power-integrated transmission mechanism that can provide six basic operating modes that can be further classified into 15 sub-modes. Switching clutch conditions helps transmission achieve speed and torque coupling. The proposed mechanism has CVT capability and an extended range capacity, and it is applicable to front-wheel-drive, rear-wheel-drive, or four-wheel-drive HEVs. A performance simulation on power and economy via Matlab and Cruise software demonstrates that the performance of the proposed transmission mechanism meets the target. Therefore, the mechanism is a feasible candidate for use in HEVs.

The minibrain kinase (Mnbk)/dual specificity Yak 1-related kinase 1A (Dyrk1A) gene is implicated in the mental retardation associated with Down's syndrome. It encodes a proline-directed serine/threonine kinase whose function has yet to be defined. We have used a solid-phase Mnbk/Dyrk1A kinase assay to aid in the search for the cellular Mnbk/Dyrk1A substrates. The assay revealed that rat brain contains two cytosolic proteins, one with a molecular mass of 100 kDa and one with a molecular mass of 140 kDa, that were prominently phosphorylated by Mnbk/Dyrk1A. The 100-kDa protein was purified and identified as dynamin 1. The conclusion was further supported by evidence that a recombinant glutathione S-transferase fusion protein containing dynamin isoform 1aa was phosphorylated by Mnbk/Dyrk1A. In addition to isoform 1aa, Mnbk/Dyrk1A also phosphorylated isoforms 1ab and 2aa but not human MxA protein when analyzed by the solid-phase kinase assay. Upon Mnbk/Dyrk1A phosphorylation, the interaction of dynamin 1 with the Src homology 3 domain of amphiphysin 1 was reduced. However, when Mnbk/Dyrk1A phosphorylation was allowed to proceed more extensively, the phosphorylation enhanced rather than reduced the binding of dynamin 1 to amphiphysin 1. The result suggests that Mnbk/Dyrk1A can play a dual role in regulating the interaction of dynamin 1 with amphiphysin 1. Mnbk/Dyrk1A phosphorylation also reduced the interaction of dynamin with endophilin 1, whereas the same phosphorylation enhanced the binding of dynamin 1 to Grb2. Nevertheless, the dual function of Mnbk/Dyrk1A phosphorylation was not observed for the interaction of dynamin 1 with endophilin 1 or Grb2. The interactions of dynamin with amphiphysin and endophilin are essential for the formation of endocytic complexes; our results suggest that Mnbk/Dyrk1A may function as a regulator controlling the assembly of endocytic apparatus.

Synthetic deoxyoligonucleotides and phosphorothioate-capped oligonucleotides targeted to bases 112–128 of β-amyloid peptide precursor (βAPP) mRNA were analyzed for their ability to reduce steady-state βAPP in COS-7 cells and in pMEP4-Rz1 cells that express a hammerhead ribozyme targeted to bases βAPP mRNA 133–148. Cells, incubated in the presence of 10 or 25 μM oligonucleotide, remained viable and morphologically identical to untreated control cells for up to 5 days. Antisense deoxyoligonucleotides β112C, β114C, and β116C specifically lowered βAPP in pMEP4-Rz1 cells compared to noncognate and scrambled oligonucleotide controls. The extent of the βAPP reduction did not depend on oligonucleotide length, although it did depend on the presence and proximity of the ribozyme to the oligonucleotides. β117N, a phosphorothioate-capped antisense oligonucleotide, also reduced βAPP levels in pMEP4-Rz1 cells; however, in this case the sense control, β117S, affected βAPP similarly, indicating that the observed reduction may be nonspecific. These data imply that deoxyoligonucleotides targeted immediately upstream of a ribozyme binding site can work cooperativelyin vivo.Localizing the oligonucleotides and ribozyme and substrate targets to the same cellular pools further confirmed this possibility.

The modification ofE.colielongation factor Ts (EF-Ts) by NEM and other sulfhydryl reagents inactivates the protein's ability to bind EF-Tu·GDP and to catalyze GDP exchange. The reactive residue was found to be Cys-22. Replacement of Cys-22 by Ser or Gly only partially impairs the binding or catalytic properties of EF-Ts while it completely protects EF-Ts from the inactivation by NEM. Cys-22 of EF-Ts is not located at the EF-Ts·EF-Tu interface, yet it can be modified only when EF-Ts is not bound to EF-Tu. These results support the proposal that the conformation change around Cys-22 in the amino terminus of EF-Ts rather than Cys-22 itself is essential for binding EF-Tu. Apparently, modification of Cys-22 by NEM disrupts the conformation change and inactivates EF-Ts. The return of EF-Ts to its native conformation may provide the driving force for the rate-determining step in the catalytic cycle, the dissociation of EF-Ts from EF-Tu·GNP.

v-H-Ras harboring the Gly-60 to Ala mutation (G60A) lacks the ability to induce germinal vesicle breakdown in Xenopusoocytes. Moreover, this mutant is capable of inhibiting the activity of v-H-Ras to induce oocyte germinal vesicle breakdown when co-injected. The duration and the extent of inhibition depends on the molar ratio of v-H-Ras(G60A) to v-H-Ras. The inhibition is not due to a general toxicity of v-H-Ras(G60A) to oocytes because oocytes injected with v-H-Ras(G60A) can be readily induced to mature by other mitogenic agents, such as insulin, insulin-like growth factor 1, insulin-like growth factor 2, and phosphatidylcholine-specific phospholipase C. The dominant negative effect of v-H-Ras(G60A) requires proper membrane attachment of v-H-Ras(G60A). By using a competition assay, it was concluded that the dominant negative phenotype of v-H-Ras(G60A) resulted from sequestering H-Ras downstream effector(s). Raf-1 was identified as one of the sequestered targets.