摘要:

AbstractVitellins were identified, purified, and analyzed from insects representing eight orders. The structures and polypeptide constituents of vitellins ofHyalophora cecropia, Tenebrio molitor, Rhodnius prolixus, Forficula auricularia, Periplaneta americana, and a mayfly were found to have common features. The native proteins had Mrof 385,000–470,000 (385–470 K) and were composed of high (100–180 K) and low (47–84 K) molecular weight polypeptides in equimolar proportions. The vitellins ofApis mellifera, a sphecid wasp, andAedes aegypti, however, had lower Mr(200–350 K) and were composed of only large polypeptides (170–190 K). The higher Diptera form a distinct third group with vitellins made up entirely of small polypeptides of

ISSN:0022-104X    

DOI:10.1002/jez.1402200102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractThe primary products of translation of the vitellins ofHyalophora cecropia, Tenebrio molitor, andAedes aegyptiwere identified by pulse‐chase labeling in fat body incubated in vitro, specific antisera being used to identify the immunospecific products. The vitellogenin ofH. cecropiawas found to be synthesized as a polypeptide of 220,000 daltons (220 K), which was cleaved to yield two polypeptides of 180 K and 47 K. The immunoprecipitable polypeptides secreted into the media during a 3‐hour culture were also 180 K and 47 K. The vitellogenin ofT. molitorwas synthesized as 204 K primary translation products, which were cleaved to yield polypeptides of 160 K, 56 K, and 45 K.A. aegyptivitellogenin differed from thoseH. cecropiaandT. molitorin that the protein was synthesized as two closely migrating polypeptides of about 170 K, which were not cleaved prior to secretion. RNA from blood‐fed femaleA. aegyptidirected the synthesis of polypeptides, in the rabbit reticulocyte cell‐free protein synthesizing system, which were of similar weight to the vitellin polypeptides. These results, taken together with data published elsewhere on certain higher Diptera, support the division of insect vitellins into three broad structural groups, as already proposed (Harnish and White

ISSN:0022-104X    

DOI:10.1002/jez.1402200103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractThe development of malformations was studied in palleal buds of the polystyelid ascidian,Polyandrocarpa misakiensis. Various malformations were induced by transection of protruding buds. Three types could be distinguished: zooids with reversed bilateral asymmetry, zooids with double malformations, and zooids with three apertures. During the early developmental stages of transected proximal pieces, when depigmentation occurred in the distal area, the pieces produced zooids with reversed bilateral asymmetry. When depigmentation occurred in the distal and proximal areas, the pieces induced either zooids with double malformations or zooids with three apertures. In the former, the two depigmented areas were about the same size, whereas in the latter the two areas were very different in size. The individuals occurring from the depigmented proximal area had the same polarity as the parent. Individuals derived from the depigmented distal area displayed either reversal of the left‐right (L‐R) axis (reversed laterality) or reversal of the L‐R and anteroposterior (A‐P) axes (normal laterality). The malformed zooid with reversed L‐R axis produced buds with reversed laterality. We examined the frequency of induction of these malformed zooids in relation to the following four points: 1) the position of the parent body at which buds are produced, 2) the different developmental stages of blastogenesis, 3) the different levels along the maximum protruding bud, and 4) the different transecting times of the maximum protruding bud. The results are discussed in relation to the mechanism of the expression of polarity in the normal development of the pa

ISSN:0022-104X    

DOI:10.1002/jez.1402200104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractThe rate of oxygen consumption (V̇ O 2) varies throughout metamorphosis in larvae of anuran amphibians. To determine whether variation in V̇ O 2is best explained by variation in developmental stage (S), dry body mass (M), or their interaction, I measured V̇ O 2in developmental series of four species. In all species M accounted for most (59–90%) of the variation in V̇ O 2. Developmental stage has relatively little effect on V̇ O 2after appropriate correction for differences in M among samples; S accounted for no more than 2% of the variation in V̇ O 2in two genera (Bufo,Rana) and no more than 7% in a third (Hymenochirus). Late stages of metamorphosis were not examined in these larvae. InXenopuslarvae, S has little effect upon V̇ O 2until late stages of metamorphosis, in which some but not all larvae had reduced V̇ O 2. The general relationship between V̇ O 2and M in anuran larvae at 25°C is V̇ O 2= 3.1 M0.827, where V̇ O 2is in μl O2STPD ·hr−1and M is in mg. Because the exponent of M, 0.827, is less than 1.0, expression of V̇ O 2as V̇ O 2·M−1fails to correct for differences in M in statistical analyses. Most prior studies of larval V̇

ISSN:0022-104X    

DOI:10.1002/jez.1402200105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractA miniature cuvette pressure chamber for microscopy and highspeed (400 frames per second) cinephotographic recordings was developed to study intracellular bubble formation inTetrahymena. The investigations show, for the first time, that intracellular bubble formation can occur, but only when the nitrogen gas supersaturations are higher than 150 atm. However, substantial fractions of the cell populations remain unaffected by exposures to gas supersaturations as high as 200 atm.

ISSN:0022-104X    

DOI:10.1002/jez.1402200106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractThe size of the metathoracic dorsal longitudinal flight muscle (DLM) in the cricketTeleogryllus oceanicusremains a constant proportion of metathoracic volume during most of nymphal life. Between the middle of the last nymphal instar and the fifth day of adult life, the DLM grows more rapidly than the metathorax, so that the ratio of DLM weight to metathoracic volume increases by a factor of 4. During this time, the DLM changes in appearance from translucent to pink, indicating an increase in mitochondrial content. Isometric twitch duration remains unchanged through late nymphal and early adult life (21 msec, onset to 50% relaxation, 25°C), as does fusion frequency (approximately 100 Hz, 25°C). During late adult life, DLM size decreases to 13% of the average for a young adult, isometric twitch duration doubles, and the DLM changes in appearance from pink to white. Since the flight motor program develops late in nymphal life and wings are produced only at the terminal molt, contraction kinetics that are characteristic of adult flight muscles appear to develop before the DLM receives the neural activity pattern for or becomes functional in flight. The appearance of adult contraction kinetics is apparently controlled by factors different from those that control increase in muscle size and mitochondrial content, since these processes are temporally separated during developmen

ISSN:0022-104X    

DOI:10.1002/jez.1402200107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractThe alleles at the agouti locus in the mouse determine whether eumelanin or pheomelanin is synthesized by the follicular melanocytes. The agouti suppressor (As) mutation, which is closely linked to the agouti locus, reduces the amount of pheomelanin produced by whatever agouti alleles are present in the animal's genome. Previous developmental studies have indicated that the agouti alleles exert their influence on the follicular melanocytes via interactions between the developing dermis and epidermis. Using the techniques of dermal‐epidermal recombination of embryonic agouti suppressor (AsAw/AsAw), white‐bellied agouti (Aw/Aw), yellow (Ay/a), viable yellow (Auy/Auy), black and tan (at/at), and nonagouti (a/a) mouse skin, the present study demonstrates that 1) the dermis is responsible for the development of regional pigmentation patterns in white‐bellied agouti mice, and 2) the agouti suppressor mutation interferes with the expression of the white‐bellied agouti allele by acting on the dermis as well as the epidermis. In addition, this study provides further evidence for the role of the epidermis in the expression of the agouti locus

ISSN:0022-104X    

DOI:10.1002/jez.1402200108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractRabbit antisera capable of detecting chicken fetal antigen (CFA) was prepared against 1‐day chick red blood cells (RBCs) and made specific by exhaustive adsorption with adult chicken peripheral RBCs (PRBCs) from the same strain. Microcytotoxicity was used to study the incidence of CFA on lymphocytes obtained from several organs at different developmental stages in the chicken. Lymphocyte‐associated CFA (LA‐CFA) determinants and erythrocytespecific CFA (ES‐CFA) determinants were distinguished through the use of adsorption analysis. The high incidence of CFA‐positive lymphocytes found in the fetal bursa and thymus was not equaled in the peripheral organs of the spleen, cecal tonsils, and gland of Harder. CFA expression on adult lymphocytes was restricted to the thymus and peripheral blood. It is suggested that these cells may represent a subpopulation of T lymphocytes. Adult spleen, cecal tonsils, and gland of Harder were virtually devoid of CFA‐bearing lymphocytes. At fetal developmental stages when greater than 94% of the bursal B cells were CFA‐positive, few, if any, of the highly differentiated Harderian B cells possessed CFA. It is suggested that LA‐CFA expression is dependent upon B cell differentiation and/or the bursa (central) vs gland of Harder (peripheral) microenvironment. The pattern of CFA expression on bursacytes is discussed in light of the properties of age resistance and bursal‐dependent target cells associated with virally induced

ISSN:0022-104X    

DOI:10.1002/jez.1402200109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractTotal phospholipid and its components were measured in lungs of the embryonic chick, and in tissue, lamellar bodies, and lavage fluid after hatching. Phosphatidylcholine (PC), the major phospholipid in surfactant, was fractionated and the amount and fatty acid composition of its disaturated (DSPC) component was determined. The synthetic rates of PC, DSPC, and other choline phospholipids were determined on days 14 and 19 of incubation from incorporation of14C‐choline. Choline pool size was also estimated at these times. Phospholipid content of the lung increased most rapidly after day 18 of incubation with the greatest increase in PC. The PC synthesized just prior to breathing was enriched in DSPC, which constituted 45% of PC on day 19 and only 30% on day 14. DSPC content was even lower in embryonic liver and yolk. Incorporation of14C‐choline in vitro into pulmonary PC, Sphingomyelin (Sphingo), and DSPC was greater in birds before breathing (day 19) than in the younger embryos. Choline pool size decreased between days 14 and 19 of incubation, but the synthetic rate of DSPC doubled in this interval. Increased accumulation and biosynthesis of pulmonary PC, Sphingo, and DSPC in lung tissue of the embryo paralleled appearance of lamellar bodies. In 5–6‐week‐old chickens the major pulmonary phospholipid was also DSPC. In lavage, 70% of PC was DSPC, predominantly dipalmitoyl PC. As in the mammalian lung, PC, especially its DSPC component, forms the major phospholipid of avian surfactant, and the synthesis of DSPC is specifically stimulated prior to

ISSN:0022-104X    

DOI:10.1002/jez.1402200110

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractThe bean‐shaped accessory glands of male mealworm beetles are morphologically complex. Seven distinct cell types produce a semisolid secretory mass that contains structural proteins of the spermatophore. Cell numbers increase 3.5‐fold over the pupal instar, and gland volume increases 30‐fold over the pupal and early adult stage. DNA content reaches its maximum at adult ecdysis (11 pg/secretory cell), RNA at 4 days later (55 pg/cell), and protein at 6 days after ecdysis (1,200 pg/cell). Rates of14C‐ and3H‐leucine incroporation increase in parallel to the rise in protein content. Over ten putative secretory protein bands were identified by using one‐dimensional SDS‐slab gel electrophoresis to compare BAG homogenates with homogenates of the secretory mass and the spermatophore. At least five of these secretory proteins accumulate in BAGs after adult ecdysis, and most show high rates of leucine incorporation in the adult. Twodimensional gel electrophoresis (pI and SDS) and fluorography allowed us to identify a score of reference spots, at least seven spots that are characteristic of the pupa, and over 40 spots that appear to be differentiation‐specific and are presumably secretory products. The fluorographic indices give an unambiguous means of scoring terminal differentia

ISSN:0022-104X    

DOI:10.1002/jez.1402200111

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY