Dev114769 218..228
نویسندگان
چکیده
During skeletal muscle development, nuclei move dynamically through myotubes in a microtubule-dependent manner, driven by the microtubule motor protein kinesin-1. Loss of kinesin-1 leads to improperly positioned nuclei in culture and in vivo. Two models have been proposed to explain how kinesin-1 functions to move nuclei in myotubes. In the cargomodel, kinesin-1 acts directly from the surfaceof the nucleus, whereas in an alternative model, kinesin-1 moves nuclei indirectly by sliding anti-parallel microtubules. Here, we test the hypothesis that an ensemble of Kif5B motors acts from the nuclear envelope to distribute nuclei throughout the length of syncytial myotubes. First, using an inducible dimerization system, we show that controlled recruitment of truncated, constitutively active kinesin-1 motors to the nuclear envelope is sufficient to prevent the nuclear aggregation resulting fromdepletion of endogenous kinesin-1.Second, we identify a conserved kinesin light chain (KLC)-binding motif in the nuclear envelope proteins nesprin-1 and nesprin-2, and show that recruitment of the motor complex to the nucleus via this LEWDmotif is essential for nuclear distribution. Together, our findings demonstrate that the nucleus is a kinesin-1 cargo in myotubes and that nesprins function as nuclear cargo adaptors. The importance of achieving and maintaining proper nuclear position is not restricted to muscle fibers, suggesting that the nesprin-dependent recruitment of kinesin-1 to the nuclear envelope through the interaction of a conserved LEWD motif with kinesin light chain might be a general mechanism for cell-typespecific nuclear positioning during development.
منابع مشابه
Bacterial scission of ether bonds.
INTRODUCTION .......................................................................................................................................................216 PROBLEM POLLUTANTS AND ETHER SCISSION..........................................................................................217 Agrochemicals........................................................................................
متن کاملExtended spectrum of HIV-1 reverse transcriptase mutations in patients receiving multiple nucleoside analog inhibitors.
OBJECTIVE To characterize reverse transcriptase (RT) mutations by their association with extent of nucleoside RT inhibitor (NRTI) therapy. To identify mutational clusters in RT sequences from persons receiving multiple NRTI. DESIGN A total of 1210 RT sequences from persons with known antiretroviral therapy were analyzed: 641 new sequences were performed at Stanford University Hospital; 569 we...
متن کاملTable DP-1. Profile of General Demographic Characteristics: 2000 Geographic area: Oliver Springs town, Tennessee
Under 5 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207 6.3 5 to 9 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218 6.6 10 to 14 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 6.0 15 to 19 years . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 6.9 20 to 24 years . . . . . . . . . . . . . . . . . . . . ....
متن کاملThe structure of SS-228Y, an antibiotic from Chainia Sp.
As reported in a previous paper1), SS-228 Y is an antibiotic produced by an actinomycete, Chainia sp. The antibiotic is active against Gram-positive bacteria and inhibits dopamine /9hydroxylase. In this paper, the structural studies on SS-228Y and a derivative, SS-228 R obtained from its photolysis or thermolysis are described. SS-228 Y (I) is an orange powder [m.p. 256-266°C, dec., [a]D-85° (c...
متن کاملChapter 16 – Emerging Viral Diseases: Why We Need to Worry about Bats, Camels, and Airplanes
Chapter Outline 1. How Do New Viral Diseases Emerge? 215 1.1 Discovery of the Etiology of an Existing Disease 215 1.2 Increase in Disease Caused by an Existing Virus 216 1.3 Accumulation of Susceptible Hosts and Viral Reemergence 217 1.4 Virus New to a Specific Population 217 2. Zoonotic Infections as a Source of Emerging Viral Diseases 217 2.1 Dead-end Hosts 217 2.2 Limited Spread among Humans...
متن کامل