Passage
Adeno-associated virus 2 (AAV2) is a nonpathogenic, nonenveloped DNA virus that requires helper viruses such as adenovirus (AV) or herpes simplex virus (HSV) to replicate efficiently. Because it can transduce human cells, including quiescent (nondividing) cells, without causing disease, AAV2 is attractive as a gene therapy vector. In clinical trials, a modified AAV2 virus has successfully treated the retinal disease Leber's congenital amaurosis as well as the blood clotting disorder hemophilia B. AAV2 transduces cells via a multistep process, shown in Figure 1.
Figure 1 Schematic showing the mechanism of transduction by AAV2Studies indicate that unlike AV and HSV, AAV2 inhibits pathways other than the endosomal pathway, such as trafficking to the Golgi, increasing the percentage of invading virus particles that arrive at the nucleus.
Adapted from Xiao PJ, Samulski RJ. Cytoplasmic trafficking, endosomal escape, and perinuclear accumulation of adeno-associated virus type 2 particles are facilitated by microtubule network. J Virol. 2012;86(19) :10462-73.
-In quiescent cells, early endosomes containing AAV2 would most likely move toward:

Question

Passage
Adeno-associated virus 2 (AAV2) is a nonpathogenic, nonenveloped DNA virus that requires helper viruses such as adenovirus (AV) or herpes simplex virus (HSV) to replicate efficiently. Because it can transduce human cells, including quiescent (nondividing) cells, without causing disease, AAV2 is attractive as a gene therapy vector. In clinical trials, a modified AAV2 virus has successfully treated the retinal disease Leber's congenital amaurosis as well as the blood clotting disorder hemophilia B. AAV2 transduces cells via a multistep process, shown in Figure 1.

Figure 1 Schematic showing the mechanism of transduction by AAV2Studies indicate that unlike AV and HSV, AAV2 inhibits pathways other than the endosomal pathway, such as trafficking to the Golgi, increasing the percentage of invading virus particles that arrive at the nucleus.
Adapted from Xiao PJ, Samulski RJ. Cytoplasmic trafficking, endosomal escape, and perinuclear accumulation of adeno-associated virus type 2 particles are facilitated by microtubule network. J Virol. 2012;86(19) :10462-73.
-In quiescent cells, early endosomes containing AAV2 would most likely move toward:

Quizplus · Accepted Answer

11ecba2d_0ff0_b378_a3bf_81a1080ea7c8_MD0008_00 The cytoskeleton is an intracellular scaffolding network of fibers that are interspersed throughout the cytoplasm. It functions to give the cell its shape, support cellular motility, and help organize intracellular components. The three major cytoskeletal components are actin filaments (ie, microfilaments), intermediate filaments, and microtubules. Microtubules are composed of alternating α- and β-tubulin subunits that assemble into hollow tubes. They are involved in various forms of movement within the cell; microtubules form the mitotic spindle during cell division and are essential for cell motility as they form the core of cilia and flagella. Microtubules also facilitate transport of vesicles such as endosomes and other organelles from one location in the cell to another. The microtubules involved in intracellular transport originate near the nucleus on small organelles called centrioles and radiate out toward the plasma membrane. The passage indicates that endosomes containing AAV2 move along microtubule tracks toward the nucleus. Because AAV2 enters the cell at the plasma membrane and moves along microtubules toward the nucleus, the endosomes that carry it must be moving toward the centrioles near the nucleus. (Choice A) Ribosomes are the enzymes that synthesize proteins during translation. They are found throughout the cytosol and on the rough endoplasmic reticulum but are not involved in trafficking along microtubules. (Choice C) Microtubules are involved in cilia formation. However, cilia are found at the edge of the cell, and the endosomes are moving away from the edge and toward the nucleus in the central region of the cell. (Choice D) A centromere is the part of a chromosome to which spindle fibers, made of microtubules, attach during metaphase of mitosis. However, quiescent (nondividing) cells are in the G₀ phase of the cell cycle, and therefore do not have organized centromeres because the chromosomes are uncoiled and relatively unstructured in this phase. Educational objective: The cytoskeleton consists of actin filaments (microfilaments), intermediate filaments, and microtubules. Microtubules are involved in intracellular transport. The microtubules involved in this process originate near the nucleus on organelles called centrioles and radiate out toward the plasma membrane.

Passage Adeno-Associated Virus 2 (AAV2) Is a Nonpathogenic, Nonenveloped DNA Virus