scholarly journals Synthesis, transport, and utilization of specific flagellar proteins during flagellar regeneration in Chlamydomonas.

1982 ◽  
Vol 93 (3) ◽  
pp. 615-631 ◽  
Author(s):  
S P Remillard ◽  
G B Witman

We labeled gametes of Chlamydomonas with 10-min pulses of 35SO4(-2) before and at various times after deflagellation, and isolated whole cells and flagella immediately after the pulse. The labeled proteins were separated by one- or two-dimensional gel electrophoresis, and the amount of isotope incorporated into specific proteins was determined. Individual proteins were identified with particular structures by correlating missing axonemal polypeptides with ultrastructural defects in paralyzed mutants, or by polypeptide analysis of flagellar fractions. Synthesis of most flagellar proteins appeared to be coordinately induced after flagellar amputation. The rate of synthesis for most quantified proteins increased at least 4- to 10-fold after deflagellation. The kinetics of synthesis of proteins contained together within a structure (e.g., the radial spoke proteins [RSP] ) were frequently similar; however, the kinetics of synthesis of proteins contained in different structures (e.g., RSP vs. alpha- and beta-tubulins) were different. Most newly synthesized flagellar proteins were rapidly transported into the flagellum with kinetics reflecting the rate of growth of the organelle; exceptions included a central tubule complex protein (CT1) and an actinlike component, both of which appeared to be supplied almost entirely from pre-existing, unlabeled pools. Isotope dilution experiments showed that, for most quantified axonemal proteins, a minimum of 35-40% of the polypeptide chains used in assembling a new axoneme was synthesized during regeneration; these proteins appeared to have predeflagellation pools of approximately the same size relative to their stoichiometries in the axoneme. In contrast, CT1 and the actinlike protein had comparatively large pools.

1977 ◽  
Vol 146 (5) ◽  
pp. 1261-1279 ◽  
Author(s):  
P P Jones

Mouse lymphocyte H-2 and Ia glycoproteins have been analyzed with a two-dimensional (2-D) acrylamide gel electrophoresis technique, in which proteins are separated first according to their charge in isoelectrofocusing gels and then according to their size in sodium dodecyl sulfate gels. Individual polypeptide chains from radiolabeled cells are resolved as discrete spots on autoradiograms of the gels, forming patterns which are characteristic of the proteins in the sample. 2-D gels of H-2K, H-2D, and Ia glycoproteins immunoprecipitated from 35S-methionine-labeled cells reveal that these proteins exist in the cells as complex arrays of molecules heterogeneous in both size and charge. Lactoperoxidase-catalyzed radioiodination of lymphocyte surfaces labels only subsets of the total H-2 and Ia molecules with 125I, indicating that some of the molecules may represent cytoplasmic precursors of the cell surface proteins. This theory is supported by the kinetics of labeling of various spots in 35S-methionine pulse-chase experiments. The 2-D gel patterns obtained for both H-2 and Ia antigens have also been shown to be haplotype-specific and independent of the genetic background.


1984 ◽  
Vol 4 (3) ◽  
pp. 424-434
Author(s):  
J A Schloss ◽  
C D Silflow ◽  
J L Rosenbaum

Flagellar amputation in Chlamydomonas reinhardtii induces the accumulation of a specific set of RNAs, many of which encode flagellar proteins. We prepared a cDNA clone bank from RNA isolated from cells undergoing flagellar regeneration. From this bank, we selected clones that contain RNA sequences that display several different patterns of abundance regulation. Based on quantitation of the relative amounts of labeled, cloned cDNAs hybridizing to dots of RNA on nitrocellulose filters, the cloned sequences were divided into five regulatory classes: class I RNAs remain at constant abundance during flagellar regeneration; classes II, III, and IV begin to increase in abundance within a few minutes after deflagellation, reach maximal abundance at successively later times during regeneration, and return to control cell levels within 2 to 3 h; and class V RNA abundance decreases during flagellar regeneration. Alpha- and beta-tubulin mRNAs are included in regulatory class IV. The abundance kinetics of alpha-tubulin mRNAs differ slightly from those of beta-tubulin mRNAs. The availability of these clones makes possible studies on the mechanisms controlling the abundance of a wide variety of different RNA species during flagellar regeneration in Chlamydomonas.


1993 ◽  
Vol 104 (3) ◽  
pp. 629-638 ◽  
Author(s):  
H. Hattori ◽  
T. Kaneda ◽  
B. Lokeshwar ◽  
A. Laszlo ◽  
K. Ohtsuka

We have previously reported that a novel 40 kDa protein is induced by heat shock and several environmental stresses in mammalian and avian cells and that the N-terminal amino acid sequence of this 40 kDa protein has homology with the bacterial DnaJ heat-shock protein. We have purified this protein (40 kDa heat-shock protein, hsp40) from HeLa cells by modified two-dimensional gel electrophoresis and generated a polyclonal antibody against hsp40. This antibody was highly specific for human hsp40 and cross-reacted weakly with rat and Chinese hamster hsp40. Indirect immunofluorescence revealed that the hsp40 in HeLa cells accumulates in the nucleus, especially in the nucleolus, during heat shock and returns to the cytoplasm during the recovery period. The kinetics of the accumulation in the nucleoli and subsequent return to the cytoplasm of hsp40 was similar to that of hsp70. In addition, hsp40 was co-localized with hsc70(p73) in heat-shocked HeLa cells as demonstrated by double immunofluorescence staining. These results suggest that hsp40 (a DnaJ homologue) and hsp70 (a DnaK homologue) may act in concert to repair (refold) denatured proteins and protein aggregates in the nuclei and nucleoli of heat-shocked HeLa cells.


In the recent past, two dimensional gel electrophoresis has emerged as a powerful molecular biology tool for the comparative expression profiling of complex protein sample. It involves the separation as well as the resolution of diverse proteins sample on the basis of isoelectric points and molecular mass of protein in two dimension ways. In this way, it reflects the view of overall proteome status including differentiation in protein expression levels, post-translational modifications etc. Moreover, this allows the identification of novel biological signatures, which may give a particular identity of pathological background to cells or tissues associated with various types of cancers and neurological disorders. Therefore, by utilizing such tools, one can clearly investigate and compare the effects of particular drugs on cells of tissues and also one can analyze the effects of disease on the basis of variations in protein expression profile at broad spectrum. Recently, to get more error-less and accurate proteome profile, conventional 2-D gel electrophoresis has been enhanced with the inclusion of different types of protein labeling dyes which enables a more comparative analysis of diverse protein sample in a single 2-D gel. In this advanced technique (2-D-DIGE), protein samples are labeled with three different types of CyDyes (Cy2, Cy3, and Cy5) separately and combined and further resolved on the same gel. This will facilitate the more accurate spot matching on a single gel platform and will also minimize the experimental variations as commonly reported in the conventional 2D-gel electrophoresis. Therefore, in the present proteomic research era, 2D-DIGE has proved to be an extremely powerful tool with great sensitivity for up to 125 ng of proteins in clinical research volubility especially, neurological and cancer related disorders.


2000 ◽  
Vol 7 (2) ◽  
pp. 301-306 ◽  
Author(s):  
Helena Enroth ◽  
Thomas Åkerlund ◽  
Anna Sillén ◽  
Lars Engstrand

ABSTRACT Strain variations of Helicobacter pylori have been tested by numerous methods and compared among different patient groups. The aim of this study was to investigate whether H. pyloriexpresses disease-specific proteins that can be detected by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). H. pylori strains isolated from duodenal ulcer, gastric cancer, and gastritis patients were analyzed. Extensive variation in spot patterns was observed between the strains, but a dendrogram analysis revealed that some strains within each disease group clustered together. Eight proteins were sequenced and found in the H. pylori genome sequence. 2-D PAGE is a useful method for studies of protein expression and for highlighting the extensive strain variation that H. pylori exhibits.


1983 ◽  
Vol 3 (10) ◽  
pp. 1866-1881
Author(s):  
J D White ◽  
J Bruno ◽  
J J Lucas

Conditions for the preparation, purification, and maintenance of karyoplasts which could regenerate to reform whole viable cells were defined. Results of biochemical analyses of such karyoplasts at various times during regeneration indicated that a reproducible biosynthetic program was followed. Thus, an examination of the polypeptides made during regeneration by two-dimensional gel electrophoresis showed that the pattern of radiolabeled polypeptides synthesized at each time studied was specific and was significantly different from that observed at other times during regeneration. Polypeptides associated with three major cellular fractions--nuclear, cytoskeletal-microtrabecular, and soluble--were among the most dramatically regulated molecules. Other polypeptides, such as the major components of microfilaments and intermediate filaments, were synthesized at relatively constant rates and were assembled into structures throughout regeneration. Likewise, microtubules appeared to be reformed throughout regeneration, even in the absence of identifiable centriole-associated organizing centers. Finally, analysis of DNA synthesis by autoradiography showed that, even when prepared from whole cells synchronized at the G1/S interface, karyoplasts could not begin making DNA until they had regenerated an almost complete complement of cytoplasm.


1984 ◽  
Vol 4 (3) ◽  
pp. 424-434 ◽  
Author(s):  
J A Schloss ◽  
C D Silflow ◽  
J L Rosenbaum

Flagellar amputation in Chlamydomonas reinhardtii induces the accumulation of a specific set of RNAs, many of which encode flagellar proteins. We prepared a cDNA clone bank from RNA isolated from cells undergoing flagellar regeneration. From this bank, we selected clones that contain RNA sequences that display several different patterns of abundance regulation. Based on quantitation of the relative amounts of labeled, cloned cDNAs hybridizing to dots of RNA on nitrocellulose filters, the cloned sequences were divided into five regulatory classes: class I RNAs remain at constant abundance during flagellar regeneration; classes II, III, and IV begin to increase in abundance within a few minutes after deflagellation, reach maximal abundance at successively later times during regeneration, and return to control cell levels within 2 to 3 h; and class V RNA abundance decreases during flagellar regeneration. Alpha- and beta-tubulin mRNAs are included in regulatory class IV. The abundance kinetics of alpha-tubulin mRNAs differ slightly from those of beta-tubulin mRNAs. The availability of these clones makes possible studies on the mechanisms controlling the abundance of a wide variety of different RNA species during flagellar regeneration in Chlamydomonas.


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