TAILIEUCHUNG - Biochemistry, 4th Edition P54

Biochemistry, 4th Edition P54. Continuing Garrett and Grisham's innovative conceptual and organizing framework, "Essential Questions," BIOCHEMISTRY guides students through course concepts in a way that reveals the beauty and usefulness of biochemistry in the everyday world. Streamlined for increased clarity and readability, this edition also includes new photos and illustrations that show the subject matter consistently throughout the text. New end-of-chapter problems, MCAT practice questions, and the unparalleled text/media integration with the power of CengageNOW round out this exceptional package, giving you the tools you need to both master course concepts and develop critical problem-solving skills you can draw upon. | What Are the Molecular Motors That Orchestrate the Mechanochemistry of Microtubules 493 a Kinesin 1 KHC N type II Kinesin 13 MCAK M ype II I I Kinesin 14 Ncd C type I I ÔIDDD N-terminal domain Motor domain Coiled coil domain C-terminal tail domain Light chain Myosin V Motor Neck Stalk C-term FIGURE a Domain structure of kinesins myosin V and cytoplasmic dynein. b Molecular models of kinesin 1 myosin V and cytoplasmic dynein. Adapted from Vale R. molecular motor toolbox for Intracellular transport. Cell 112 467-480. 494 Chapter 16 Molecular Motors HUMAN BIOCHEMISTRY Effectors of Microtubule Polymerization as Therapeutic Agents Microtubules in eukaryotic cells are important for the maintenance and modulation of cell shape and the disposition of intracellular elements during the growth cycle and mitosis. It may thus come as no surprise that the inhibition of microtubule polymerization can block many normal cellular processes. The alkaloid colchicine see accompanying figure a constituent of the swollen underground stems of the autumn crocus Colchicum autumnale and meadow saffron inhibits the polymerization of tubulin into microtubules. This effect blocks the mitotic cycle of plants and animals. Colchicine also inhibits cell motility and intracellular transport of vesicles and organelles which in turn blocks secretory processes of cells . Colchicine has been used for hundreds of years to alleviate some of the acute pain of gout and rheumatism. In gout white cell lysosomes surround and engulf small crystals of uric acid. The subsequent rupture of the lysosomes and the attendant lysis of the white cells initiate an inflammatory response that causes intense pain. The mechanism of pain alleviation by colchicine is not known for certain but appears to involve inhibition of white cell movement in tissues. Interestingly colchicine s ability to inhibit mitosis has given it an important role in the commercial development of new varieties of agricultural and .

• Sinh học
• Nền tảng của hóa sinh học
• trao đổi chất protein
• RNA trao đổi chất
• nguyên tắc của hóa sinh
• Axit amin
• công nghệ DNA