PERSPECTIVES AND SUMMARY . . . . . 1151 CHARACTERIZATION OF THE RESPONSE 1153 Comparison: Different Organisms and Stages of Development. ll53 The Proteins Induced by Heat ... . 1155 RNAs Induced by Heat 1167 OTHER INDUCTIONS OF HSPs 1168 Developmental Inductions .. . ... . . . . . . .. .. .. . ... ...... . .... . .. . . . 1168 Other Inducers 1 1 69 Is There a Common Mechanism? ........ ... 1170 GENOME ORGANIZATION 1172 REGULATION OF THE RESPONSE 1173 Transcription 1173 Translation . . . . .. ..... ......... .. . . .. .. .. .... . .. ...... . . . .. . . . . .. .. .. . .. .. .. . . . . . . . . . 1177 RNA Processing 1178 TOLERANCE TO HEAT AND OTHER FORMS OF STRESS . . . 1179 Heat-Induced Lethality and Thermotolerance . . . . . . . . . . . . . 1179 Phenocopies 1182 CONCLUDING REMARKS 1184

The heat-shock response

characterized by its ability to produce crystalline inclusions during spor-ulation. TIhese inclusions consist of proteins exhibiting a highly specific insecticidal activity (reviewed in references 4 and 97). Many B. thuriuigiensis strains with different insect host spectra have been identified (9). TIhey ar-e classified into different serotypes or subspecies based on their flagellar antigens. Most strains are active against larvae of certain members of the Lepidoptera, but some show toxicity against dipterian (reviewed in refer-ence 22) or coleopteran (53) species. For several cryst.al-producing strains.

Insecticidal crystal proteins of Bacilllus thuringiensis

Publisher Summary This chapter focuses on the important discovery that virus-specific cytotoxic T cells are dually specific for virus and for a self cell surface antigen encoded by the major histocompatibility complex (MHC). The initial work was carried out on the lymphocytic choriomeningitis virus system but it soon became evident that the same phenomenon applied to many other viruses. In addition, the same principle has been found to hold for other antigenic systems, such as trinitrophenyl coupled to cells, minor histocompatibility antigens, and the H-Y model. Graft rejection and the need for genetically homogeneous inbred mouse strains for cancer research led to the development of transplantation immunology and immunogenetics. The result is that the gene complex coding for major transplantation antigens is one of the better understood mammalian genetic regions. Cytotoxic T-cell specificity is comparable to serological specificity. Because quantification of specificity or cross-reactivity is difficult, and because of the technical limitations of these cytotoxic T-cell assays, results are interpreted with great reservation. MHC restriction reflects the fact that the effector function of T cells is determined by the kind of Self-H recognized together with the foreign antigen on cell surfaces: K and D are receptors for lytic signals, I determinants are receptors for cell differentiation signals that are delivered antigen-specifically by T cells.

MHC-restricted cytotoxic T cells: studies on the biological role of polymorphic major transplantation antigens determining T-cell restriction-specificity, function, and responsiveness.

Publisher Summary This chapter describes methods for sodium dodecyl sulfate (SDS) gel electrophoresis and the characterization of proteins separated on SDS gels. SDS dissociates proteins into their constituent polypeptide chains. Polyacrylamide gel electrophoresis in the presence of SDS separates polypeptide chains according to their molecular weights. Thus, the size of the polypeptide chains of a given protein can be determined by comparing their electrophoretic mobilities on SDS gels to the mobilities of marker proteins with well-characterized polypeptide chain molecular weights. SDS-polyacrylamide gel electrophoresis is easily and rapidly performed, requires only inexpensive equipment, and can be used with microgram amounts of protein. The technique is both reliable and reproducible, and the results are easy to interpret. The procedure described in the chapter is designed to alkylate various functional groups of the proteins so as to maximize the likelihood of irreversible denaturation. Small changes in electrophoretic mobility may occur after such extensive alkylation.

Measurement of molecular weights by electrophoresis on SDS-acrylamide gel.

Publisher Summary This chapter describes polyacrylamide gel electrophoresis of viral proteins. Viral structural and nonstructural proteins are agents of expression for the information carried in viral nucleic acid genomes. An understanding of the behavior of a virus requires its proteins be characterized. For this purpose and for the characterization of nucleic acids, electrophoresis in gels is the most sensitive and versatile method. The genetic content and number of proteins of most viruses is relatively small compared even to simple cells. Two aspects of gels as supporting media for zonal electrophoresis experiments are responsible for the dramatic separations. First, as simple anti-convection media gels, they are more homogeneous and stable than other commonly used materials. Second, with the correct choice of gel concentrations, the spaces in the gel matrix are of similar dimensions to macromolecules so that selective sieving occurs during the electrophoretic migration. Gels composed of polyacrylamide are extensively used at the present time.

Polyacrylamide Gel Electrophoresis of Viral Proteins

Methods in Virology

What do you do to start reading aphids as virus vectors? Searching the book that you love to read first or find an interesting book that will make you want to read? Everybody has difference with their reason of reading a book. Actuary, reading habit must be from earlier. Many people may be love to read, but not a book. It's not fault. Someone will be bored to open the thick book with small words to read. In more, this is the real condition. So do happen probably with this aphids as virus vectors.

Aphids As Virus Vectors

Invertebrate systems in vitro

Publisher Summary Whitefly-borne diseases of plants cause great concern in many tropical areas. The fact that beans, soybeans, pigeon peas, and other edible legumes, which are primary sources of protein for the diet of many people in the tropics, fall prey to some of these agents who has prompted local governments and international agencies to institute programs for their study and control. Increased incidence and ample dissemination of bean yellow mosaic (BGYM) in the Pacific watersheds of Guatemala, Nicaragua, Costa Rica, and Panama were noted.. An increased incidence of diseases caused by whitefly-transmitted agents in the Western Hemisphere has been noted by Costa et al. and Costa, who postulated that in Brazil this could well be due to an abnormal augmentation in the population density of B. tabaci , the main spreader of such diseases. Bearing in mind the menace represented by these diseases and considering the role played by edible legumes and other crops as direct protein and carbohydrate sources for the population of many tropical areas of the world, the present chapter is written in the hope that it would be of help to those involved in the research with aleyrodids and the agents they transmit. Special attention is devoted in this chapter to the diseases occurring in the Western Hemisphere, particularly to those prevailing in the Caribbean and in Central and South America.

Karl Maramorosch

Papers

Methods in Virology

Aphids As Virus Vectors

Invertebrate systems in vitro

Viruses and virus diseases associated with whiteflies.

Leafhopper vectors and plant disease agents