Comparison of Interaction Modalities for Mobile Indoor Robot Guidance: Direct Physical Interaction, Person Following, and Pointing Control

We describe a new robotic assist device: the passive assist arm (PAS-Arm). PAS-Arms are intended for direct physical interaction with a human operator. PASArms are physically passive. The force to manipulate the arm end must be provided by the operator. Their purpose is not to enhance human strength, but to provide virtual guiding surfaces that constrain and guide the motion of the operator. PAS-Arms have three joints and a three dimensional workspace, but possess only two degrees of freedom due to the reduction of degrees of freedom created by a combination of Continuously Variable Transmissions (CVTs) and differential gears. In this paper, we first discuss the manipulability ellipsoid for the PAS-Arm. The major axis of the ellipsoid is the direction in which the arm end may be easily manipulated, and vice versa. We have developed an experimental system for the PAS-Arm. The CVTs of the experimental system may not adjust the transmission ratio to zero. Second, we describe an algorithm to address that problem. Finally, we present initial experiments that verify the PAS-Arm mechanism. The experimental results successfully produced virtual guiding surfaces.1 1. This paper is the full translation from the transactions of JSME, Series C, Vol.76, No.763, pp. 611-618, 2010.

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E1A-mediated inhibition of myogenesis correlates with a direct physical interaction of E1A12S and basic helix-loop-helix proteins.

Molecular and Cellular Biology ◽

10.1128/mcb.13.8.4714 ◽

1993 ◽

Vol 13 (8) ◽

pp. 4714-4727 ◽

Cited By ~ 35

Author(s):

D A Taylor ◽

V B Kraus ◽

J J Schwarz ◽

E N Olson ◽

W E Kraus

Keyword(s):

Gene Transcription ◽

Specific Gene ◽

Deletion Mutants ◽

Physical Interaction ◽

Direct Physical Interaction ◽

Amino Terminal ◽

High Affinity ◽

Basic Helix Loop Helix ◽

Helix Loop Helix ◽

E Box

The observation that adenovirus E1A gene products can inhibit differentiation of skeletal myocytes suggested that E1A may interfere with the activity of myogenic basic helix-loop-helix (bHLH) transcription factors. We have examined the ability of E1A to mediate repression of the muscle-specific creatine kinase (MCK) gene. Both the E1A12S and E1A13S products repressed MCK transcription in a concentration-dependent fashion. In contrast, amino-terminal deletion mutants (d2-36 and d15-35) of E1A12S were defective for repression. E1A12S also repressed expression of a promoter containing a multimer of the MCK high-affinity E box (the consensus site for myogenic bHLH protein binding) that was dependent, in C3H10T1/2 cells, on coexpression of a myogenin bHLH-VP16 fusion protein. A series of coprecipitation experiments with glutathione S-transferase fusion and in vitro-translated proteins demonstrated that E1A12S, but not amino-terminal E1A deletion mutants, could bind to full-length myogenin and E12 and to deletion mutants of myogenin and E12 that spare the bHLH domains. Thus, the bHLH domains of myogenin and E12, and the high-affinity E box, are targets for E1A-mediated repression of the MCK enhancer, and domains of E1A required for repression of muscle-specific gene transcription also mediate binding to bHLH proteins. We conclude that E1A mediates repression of muscle-specific gene transcription through its amino-terminal domain and propose that this may involve a direct physical interaction between E1A and the bHLH region of myogenic determination proteins.

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Coregulated human globin genes are frequently in spatial proximity when active

The Journal of Cell Biology ◽

10.1083/jcb.200507073 ◽

2006 ◽

Vol 172 (2) ◽

pp. 177-187 ◽

Cited By ~ 147

Author(s):

Jill M. Brown ◽

Joanne Leach ◽

Joyce E. Reittie ◽

Ann Atzberger ◽

Jane Lee-Prudhoe ◽

...

Keyword(s):

Higher Order ◽

Nuclear Proteins ◽

Spatial Proximity ◽

Chromosome Territories ◽

Physical Interaction ◽

Globin Genes ◽

Nuclear Speckles ◽

Direct Physical Interaction ◽

Physical Interactions ◽

Dense Chromatin

The organization of genes within the nucleus may influence transcription. We have analyzed the nuclear positioning of the coordinately regulated α- and β-globin genes and show that the gene-dense chromatin surrounding the human α-globin genes is frequently decondensed, independent of transcription. Against this background, we show the frequent juxtaposition of active α- and β-globin genes and of homologous α-globin loci that occurs at nuclear speckles and correlates with transcription. However, we did not see increased colocalization of signals, which would be expected with direct physical interaction. The same degree of proximity does not occur between human β-globin genes or between murine globin genes, which are more constrained to their chromosome territories. Our findings suggest that the distribution of globin genes within erythroblast nuclei is the result of a self-organizing process, involving transcriptional status, diffusional ability of chromatin, and physical interactions with nuclear proteins, rather than a directed form of higher-order control.

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Characterization of the direct physical interaction of nc886, a cellular non-coding RNA, and PKR

FEBS Letters ◽

10.1016/j.febslet.2012.07.076 ◽

2012 ◽

Vol 586 (19) ◽

pp. 3477-3484 ◽

Cited By ~ 35

Author(s):

Sung Ho Jeon ◽

Kwanbok Lee ◽

Kwang Soo Lee ◽

Nawapol Kunkeaw ◽

Betty H. Johnson ◽

...

Keyword(s):

Physical Interaction ◽

Direct Physical Interaction ◽

Non Coding Rna

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A Novel Signal Transduction Cascade Involving Direct Physical Interaction of the Renin/Prorenin Receptor With the Transcription Factor Promyelocytic Zinc Finger Protein

Circulation Research ◽

10.1161/01.res.0000251700.00994.0d ◽

2006 ◽

Vol 99 (12) ◽

pp. 1355-1366 ◽

Cited By ~ 227

Author(s):

Jan H. Schefe ◽

Mario Menk ◽

Jana Reinemund ◽

Karin Effertz ◽

Robin M. Hobbs ◽

...

Keyword(s):

Signal Transduction ◽

Transcription Factor ◽

Zinc Finger ◽

Zinc Finger Protein ◽

Physical Interaction ◽

Direct Physical Interaction ◽

Signal Transduction Cascade ◽

Finger Protein ◽

Prorenin Receptor

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The J Domain of Papovaviral Large Tumor Antigen Is Required for Synergistic Interaction with the POU-Domain Protein Tst-1/Oct6/SCIP

Molecular and Cellular Biology ◽

10.1128/mcb.19.4.2455 ◽

1999 ◽

Vol 19 (4) ◽

pp. 2455-2464 ◽

Cited By ~ 21

Author(s):

Elisabeth Sock ◽

Janna Enderich ◽

Michael Wegner

Keyword(s):

T Antigen ◽

Terminal Region ◽

Amino Terminus ◽

Physical Interaction ◽

Large T Antigen ◽

T Antigens ◽

Direct Physical Interaction ◽

Amino Terminal ◽

Pou Domain ◽

J Domain

ABSTRACT Large T antigens from polyomaviruses are multifunctional proteins with roles in transcriptional regulation, viral DNA replication, and cellular transformation. They have been shown to enhance the activity of various cellular transcription factors. In the case of the POU protein Tst-1/Oct6/SCIP, this enhancement involves a direct physical interaction between the POU domain of the transcription factor and the amino-terminal region of large T antigen. Here we have analyzed the structural requirements for synergistic interaction between the two proteins in greater detail. Tst-1/Oct6/SCIP and the related POU protein Brn-1 were both capable of direct physical interaction with large T antigen. Nevertheless, only Tst-1/Oct6/SCIP functioned synergistically with large T antigen. This differential behavior was due to differences in the amino-terminal regions of the proteins, as evident from chimeras between Tst-1/Oct6/SCIP and Brn-1. Synergy was specifically observed for constructs containing the amino-terminal region of Tst-1/Oct6/SCIP. Large T antigen, on the other hand, functioned synergistically with Tst-1/Oct6/SCIP only when the integrity of its J-domain-containing amino terminus was maintained. Mutations that disrupted the J domain concomitantly abolished the ability to enhance the function of Tst-1/Oct6/SCIP. The J domain of T antigen was also responsible for the physical interaction with Tst-1/Oct6/SCIP and could be replaced in this property by other J domains. Intriguingly, a heterologous J domain from a human DnaJ protein partially substituted for the amino terminus of T antigen even with regard to the synergistic enhancement of Tst-1/Oct6/SCIP function. Given the general role of J domains, we propose chaperone activity as the underlying mechanism for synergy between Tst-1/Oct6/SCIP and large T antigens.

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Tetherin/BST-2 Antagonism by Nef Depends on a Direct Physical Interaction between Nef and Tetherin, and on Clathrin-mediated Endocytosis

PLoS Pathogens ◽

10.1371/journal.ppat.1003487 ◽

2013 ◽

Vol 9 (7) ◽

pp. e1003487 ◽

Cited By ~ 40

Author(s):

Ruth Serra-Moreno ◽

Kerstin Zimmermann ◽

Lawrence J. Stern ◽

David T. Evans

Keyword(s):

Physical Interaction ◽

Direct Physical Interaction

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