Studies in the biochemistry of cirripede eggs. V. Changes in the general biochemical composition during development of Chthamalus stellatus (Poli)

The biochemical composition of the eggs of Chthamulus stellatus (Poli) during their development has been investigated. The eggs are incubated within the mantle cavity of the adult but no substrates are contributed by the latter. Carbohydrates, protein, and lipid are all utilized. In contrast to two cold-water species, Balanus balanoides and B. balanus perviously investigated lipid rather than protein is consumed during the early stages. Possible explanations for this are considered.     

Studies in the biochemistry of cirripede eggs. VI. Changes in the general biochemical composition during development of Tetraclita squamosa rufotincta Pilsbry,Balanus perforatus Brug., and Pollicipes cornucopia Darwin

The carbohydrate, protein, lipid, total RNA and DNA at four stages in the development of the eggs of Tetraclita squamosa rufotincta Pilsbry, Balanus perforatus Brug., and Pollicipes cornucopia Darwin have been determined. The initial caloric content varies with species, that of the large egg of Tetraclita being extremely high; on a relative volume-specific basis, however, differences, although still present, are much less variable. A comparison has been made with other species. Those eggs in which lipid predominates over protein in Stage I lose more lipid during development. The relatively large quantities of reserves in Tetraclita may serve as metabolic substrate during the development of the planktonic larvae under nutrient-poor conditions.     

Studies in the biochemistry of cirripede eggs. IV. The free Amino-acid pool in the eggs of Balanus balanoides (L.) and B. balanus (L.) during development

Changes in the ‘free’ amino acids, betaine, and trimethylamine oxide during the development of the eggs of Balanus balanoides (L.) and B. balanus (L.) have been determined; the results are given in terms of μM/g dry wt, μM/g water, and μM/10⁶ eggs. The amino acids are derived from the yolk proteins the net composition of which is known. Free amino acids are present in considerable quantity, as is commonly the case with crustacean tissue. Changes in the individual amino acids are discussed. B. balanus eggs contain large, and relatively constant, amounts of sarcosine; its function is unknown but large quantities are present in the more highly evolved cirripedes so far examined. A possible relation between betaine glycine, and sarcosine relative to choline metabolism is considered. Large amounts of taurine are present. There is a striking increase in β-alanine in the late stages of development; in B. balanoides it comes to be the most, and in B. balanus the third most common amino acid; its possible involvement in purine metabolism is considered. The relation between the amounts of the various entities in the eggs and in the bodies of the adult are examined.     

Changes in lipid and fatty acid composition of eggs during development of the beet armyworm, Spodoptera exigua

The dry weight of Spodoptera exigua eggs decreased by 15·9 μg/egg or 64% of initial weight during embryogenesis and development of pharate first instar larvae. Lipid depletion accounts for 36% of this total dry weight loss and this occurs at an essentially constant rate throughout development. This marks S. exigua as an exception since most insects utilize lipids more rapidly during later developmental stages. Lipid depletion is due primarily to triglyceride catabolism, although phospholipids also decrease significantly.Fatty acid composition remains stable during development. In triglycerides, 18:1 is most common followed by 16:0 and 18:2; in the phospholipids, the order of abundance is 18:1, 18:2, and 16:0. Egg fatty acids differ from dietary fatty acids: 16:1 comprises 7% of triglyceride fatty acids although it is not present in the larval media; 18:1 predominates in the egg whereas 18:2 is most abundant in the diet.     

Changes in biochemical composition of vacuoles isolated from Acer pseudoplatanus L. during cell culture

Vacuoles were isolated from Acer pseudoplatanus cell suspension culture using a one-step procedure involving the lysis of the protoplast plasmalemma through a gradient of Ficoll containing DEAE-Dextran. The vacuole suspensions were slightly contaminated by other organelles (less than 5%) and the isolated vacuoles readily accumulated neutral red. Since α-mannosidase was located exclusively in the vacuoles it was used as a convenient marker. It was shown that the number of vacuoles per protoplast decreased as the cell aged. Studies on the biochemical composition of the isolated vacuoles indicated that amino acids, organic acids and protein contents varied with the cell culture cycle, emphasizing the dynamic status of the vacuolar system in cell suspension cultures of Acer pseudoplatanus.     

Changes in the biochemical composition of Euphausia superba Dana embryos during early development

Summary The biochemical composition of developing Euphausia superba Dana embryos has been examined at three stages: fresh spawned, gastrula, and limb bud. Fresh spawn embryos had 31% lipid, 1.0% carbohydrate, and 57% protein on a gram dry weight basis. Throughout development lipids were utilized more slowly than in other crustacean embryos for a total utilization of 37.5%. Overall, 35.6% of the starting protein was utilized. On a weight basis, twice as much protein than lipid was used during development, and it appeared that, energetically, protein and lipid contributed equally to the energetics of the developing embryo. Carbohydrate was evidently a minor substrate in early development, although the level increased 38% during development. Average water content was 86% in fresh spawned embryos and 88% in the gastrula stage. The average dry weight of the embryos throughout development was 30 g. The features of planktonic embryos are contrasted with demersal embryos and the atypical metabolic pattern of krill embryos is discussed.MOA dedicates this paper to the memory of Dr. Mary Alice McWhinnie, for her encouragement during my years at DePaul University and for the opportunity to participate in her research     

Changes in biochemical composition of the cell wall of the cotton fiber during development

The composition of the cell wall of the cotton fiber (Gossypium hirsutum L. Acala SJ-1) has been studied from the early stages of elongation (5 days postanthesis) through the period of secondary wall formation, using cell walls derived both from fibers developing on the plant and from fibers obtained from excised, cultured ovules. The cell wall of the elongating cotton fiber was shown to be a dynamic structure. Expressed as a weight per cent of the total cell wall, cellulose, neutral sugars (rhamnose, fucose, arabinose, mannose, galactose, and noncellulosic glucose), uronic acids, and total protein undergo marked changes in content during the elongation period. As a way of analyzing absolute changes in the walls with time, data have also been expressed as grams component per millimeter of fiber length. Expressed in this way for plant-grown fibers, the data show that the thickness of the cell wall is relatively constant until about 12 days postanthesis; after this time it markedly increases until secondary wall cellulose deposition is completed. Between 12 and 16 days postanthesis increases in all components contribute to total wall increase per millimeter fiber length. The deposition of secondary wall cellulose begins at about 16 days postanthesis (at least 5 days prior to the cessation of elongation) and continues until about 32 days postanthesis. At the time of the onset of secondary wall cellulose deposition, a sharp decline in protein and uronic acid content occurs. The content of some of the individual neutral sugars changes during development, the most prominent change being a large increase in noncellulosic glucose which occurs just prior to the onset of secondary wall cellulose deposition. Methylation analyses indicate that this glucose, at least in part, is 3-linked. In contrast to the neutral sugars, no significant changes in cell wall amino acid composition are observed during fiber development.     

Tidal rates of settlement of the intertidal barnacles Chthamalus stellatus and Chthamalus montagui in western Europe: the influence of the night/day cycle

Chthamalus montagui and Chthamalus stellatus are abundant barnacles in western Europe. Tidal settlement of Chthamalus in SW Ireland and SW Portugal was studied in relation to a night and day factor and at different temporal (dates) and spatial (shores and sites) scales. Based on the identifiable cyprids and metamorphs, Chthamalus settlement in SW Ireland was comprised mainly of C. stellatus but was composed of C. montagui only in SW Portugal.In SW Ireland and SW Portugal, settlement rates of Chthamalus (mean number of settlers per 25 cm²±S.E.) were higher after one day tidal cycle (597±158.7 in SW Ireland, 144±23.6 in SW Portugal) than one night tidal cycle (55±12.1 in SW Ireland, 13±2.2 in SW Portugal), but significant differences were only detected in SW Portugal. Different models were proposed for explaining this pattern related to night and day variability of the physical processes responsible for transporting cyprids to shore (1), and/or of pre-settlement behaviour (2) and/or of settlement behaviour of cyprids (3).Spatial patterns of tidal settlement of both species or at both locations seem similar with small scale variability (between sites, 5 to 30 m apart) in settlement of Chthamalus being the only spatial scale at which variability was detected in both locations.The composition of Chthamalus cohorts settling during one tidal cycle differed considerably between locations/species: settlers of C. stellatus were mainly cyprids; settlers of C. montagui during the day (when most settlement occurred) were essentially metamorphs.     

渐尖毛蕨和齿牙毛蕨的配子体发育研究

采用混合土培养渐尖毛蕨和齿牙毛蕨的孢子,显微镜下观察记录了它们的孢子萌发及配子体发育过程.结果表明:两者的孢子均为深褐色,极面观为椭圆形,赤道面观为半圆形,单裂缝;渐尖毛蕨的孢子萌发所需时间较渐尖毛蕨短,但两者萌发类型均为书带蕨型;丝状体阶段均发达;原叶体边缘均可产生少量毛状体;成熟原叶体均呈心脏形;由原叶体发育成幼孢...     

Shell formation and calcium transport in the barnacle Chthamalus fragilis

The mantle epithelium of the barnacle Chthamalus fragilis (Darwin) exhibits several ultrastructural features which may serve to regulate the calcification process. At the basis-mural plate and intermural plate junctions where rapid shell growth occurs, cells are characterized by long apical cytoplasmic projections and large intercellular spaces. These features may increase the functional surface area of the epithelium and enable more rapid deposition of calcium. The cells underlying the general shell surfaces contain numerous electron-dense inclusion bodies and show frequent cellular disintegration near the growing shell interface. Release of the granular contents of these inclusion bodies has been observed in both disintegrating and non-disintegrating cells. X-ray microanalysis revealed significantly higher calcium levels in the inclusion bodies than in the surrounding cytoplasm. This suggests a calcium transport role for these inclusion bodies. Cellular debris produced as a result of the disintegration of the mantle cells near the shell may play some role in the formation of the organic matrix of the shell. The presence of large numbers of mitochondria and well-developed apical microvilli in the cells of the inner mantle epithelium suggest that these cells serve to transport calcium into the mantle from the ambient sea water.     

Changes in the biochemical composition of fat body stores during adult development of female crickets, Gryllus bimaculatus

Age-dependent changes in the fat body composition and aspects of lipogenesis in the free abdominal fat body of female crickets, Gryllus bimaculatus, were studied. Lipid, protein, glycogen, and free carbohydrate content of the fat body, and fat body wet weight increased simultaneously and sharply from day 0 onwards and were doubled/almost doubled by day 2 after adult emergence. Lipogenic activity of the fat body, fat body weight, and the energy stores in the fat body peaked on day 2, except for free carbohydrate, which peaked on day 3. On day 2, the fat body was mainly comprised of lipid (53.8%) and protein (6.6%), while glycogen and free carbohydrate together contributed less than 1% of the fat body wet weight. After peaking, both lipogenesis and energy stores decreased in a synchronous manner. The depletion of the fat body energy stores and the consequent decrease in the fat body weight were concomitant with a fast and massive gain in ovary weight (day 2: 19.5 +/- 1.5 mg; day 4: 332.8 +/- 31.5 mg) due to the vitellogenic oocyte growth that started on day 2. Our data clearly underline the importance of the free abdominal fat body as a source of energy for reproduction in the cricket. Fat body fatty acid synthase activity coincided with lipogenic activity. Adipokinetic hormone inhibits lipid synthesis in the fat body, but treatment of the fat body with adipokinetic hormone in vitro showed no consistent effect on fatty acid synthase activity.     

Studies on sex-organ development. Changes in nuclear and chromatin composition and genomic activity during spermatogenesis in the maturing rooster testis.

We developed a technique to separate nuclei of rooster testis by centrifugation through a discontinuous sucrose density gradient and by sedimentation at unit gravity. Four different major fractions obtained from testicular nuclei and one from the vas deferens were characterized according to their velocity of sedimentation, morphology and DNA content. The ratios (w/w) of basic proteins, non-histone proteins and RNA to DNA decreased during spermiogenesis both in nuclei and chromatin. Changes in the electrophoretic patterns of histones and non-histone proteins were detected especially in the elongated spermatids. The lack of uptake of [3H]uridine in elongating and elongated spermatids and in spermatozoa was demonstrated by radioautography and by the detection of labelled RNA extracted from different fractions of nuclei. Template activity for RNA synthesis and the binding of actinomycin D by testicular nuclei reached a peak in the elongated spermatid stage, when the histones are replaced by the protamine.     

Changes in the structure, composition and function of sarcoplasmic-reticulum membrane during development.

The structure, chemical composition and function of the microsomal fraction, isolated by differential centrifugation and purified on sucrose gradients, from muscle of fetal, newborn and young rabbits were characterized and compared with those of sarcoplasmic reticulum vesicles from adult muscle. Negative staining shows that the microsomal vesicles isolated from muscles of embryos and newborn animals are smooth, in contrast to vesicles obtained from adult muscle which contain 4-nm particles on their surface. The particles appear first in the microsomal vesicles from muscles of 5--8-day-old rabbits. Their number increases with the age of the animals. Ca2+-pump protein, with molecular weight about 100000, accounts for 10% of the total protein content in sarcoplasmic reticulum membrane, isolated at the earliest stages of development analysed. Its amount increases continuously with the rabbit's age to the adult value of about 70% of total sarcoplasmic reticulum protein. The low amount of 100000-dalton protein and lack of 4-nm surface particles in sarcoplasmic reticulum vesicles obtained from fetal and newborn rabbits are strictly correlated with the low activity of Ca2+-dependent ATPase and the ability to take up Ca2+. These activities rise in parallel with the age of the rabbits. On the other hand, Mg2+-dependent ATPase activity is very high at the early stages of development and declines continuously to a low value in sarcoplasmic reticulum from adult muscle. The sarcoplasmic reticulum membrane from fetal and newborn rabbits contains a higher amount of lipids as compared with the membrane present in the muscle of adult animals. The ratio of both phospholipid to protein and neutral lipid to protein decreases with the age of the rabbits. The composition of sarcoplasmic reticulum phospholipids also changes during development.     

Changes in the fatty acid composition of Drosophila melanogaster during development and ageing.

In Drosophila melanogaster the saturated fatty acids increase in amount early in pupal development relative to the concentrations in late third instar larvae, then decline to the levels characteristic of one-day-old adults. Conversely, the monounsaturated fatty acids decline in content early in pupal development, then increase late in the pupal period. Lauric acid (12:0), myristic acid (14:0) and palmitoleic acid (16:1) become more prominent and oleic acid (18:1) and palmitic acid (16:0) less prominent as the adult ages. At about 40 days of adult age myristic acid (14:0) begins to decrease and oleic acid (18:1) to increase. Within 20 days of eclosion males and females contain different amounts of myristic acid (14:0), palmitic acid (16:0) and oleic acid (18:1).     

Studies on the biochemistry and fine structure of silicia shell formation in diatoms VII. Sequential cell wall development in the pennateNavicula pelliculosa

Summary The development of the wall of synchronized culture ofN. pelliculosa is described. The first step, modification of the 3-2 configuration of the girdle bands of the wall during interphase, occurs immediately before mitotic division by the addition of a third girdl band to the hypotheca. Following cytokenesis, the new valve is initiated when a primary central band is formed within a silica deposition vesicle. This band extends the length of the cell and contains a central nodule. Secondary arms extend from the central nodule, join with extensions of the primary central band, and constitute the raphe rib. Mounds or knolls are formed on the central nodule and disappear as the valve matures. Transapical ribs appear on both the primary central band and secondary arms, and cross extensions join to form the sieve plate areas. The wall appears to be released by a joining of the inner silicalemma and the plasmalemma. An organic coat covers the newly released wall. Two girdle bands are formed and released sequentially.     

Changes in the zein composition of protein bodies during maize endosperm development.

Zeins, the seed storage proteins of maize, are synthesized during endosperm development by membrane-bound polyribosomes and transported into the lumen of the endoplasmic reticulum, where they assemble into protein bodies. To better understand the distribution of the various zeins throughout the endosperm, and within protein bodies, we used immunolocalization techniques with light and electron microscopy to study endosperm tissue at 14 days and 18 days after pollination. Protein bodies increase in size with distance from the aleurone layer of the developing endosperm; this reflects a process of cell maturation. The protein bodies within the subaleurone cell layer are the smallest and contain little or no alpha-zein; beta-zein and gamma-zein are distributed throughout these small protein bodies. The protein bodies in cells farther away from the aleurone layer are progressively larger, and immunostaining for alpha-zein occurs over locules in the central region of these protein bodies. In the interior of the largest protein bodies, the locules of alpha-zein are fused. Concomitant with the appearance of alpha-zein in the central regions of the protein bodies, most of the beta- and gamma-zeins become peripheral. These observations are consistent with a model in which specific zeins interact to assemble the storage proteins into a protein body.     

Changes in phospholipid composition during the development of Dictyostelium discoideum

The phospholipid composition of Dictyostelium discoideum cells was determined at various stages of development by two-dimensional, thin-layer chromatography and reaction thin-layer chromatography. Major phospholipids of D. discoideum which were detectable throughout all stages of development were ethanolamine phosphoglyceride and choline phosphoglyceride. Ethanolamine phosphoglyceride and choline phosphoglyceride were found as their plasmalogen forms at 45–58 and 10–24%, respectively. There were no qualitative changes in phospholipid composition during the development, but quantitative changes did occur. The relative content of ethanolamine phosphoglyceride in the total phospholipids gradually decreased from 60% at the vegetative stage to 44% at the 1-day-sorocarp stage. In contrast, choline phosphoglyceride gradually increased from 27% at the vegetative stage to 48% at the preculmination stage, and then gradually decreased to 43% during the culmination. The decrease in ethanolamine phosphoglyceride content during the middle and late development was due mainly to the decreased amount of its plasmalogen form but the increase of choline phosphoglyceride was independent of quantitative changes of its plasmalogen form. Other minor components of phospholipid did not show significant changes in their levels. The causes of these changes in contents of ethanolamine phosphoglyceride and choline phosphoglyceride were examined by label and chase experiments with [³H]ethanolamine and [¹⁴C]choline. It seems that one-third to one-half of the increased amount of choline phosphoglyceride was due to stepwise methylation of ethanolamine phosphoglyceride, and the remaining two-thirds to one-half was caused by de novo synthesis of choline phosphoglyceride from CDP-choline and diglyceride.     

半滑舌鳎受精卵、卵黄囊仔鱼和开口仔鱼氨基酸及脂肪酸的变化

采用气相色谱仪和氨基酸分析仪测定了半滑舌鳎(Cynoglossus semilaevis)受精卵、卵黄囊仔鱼和开口仔鱼的氨基酸与脂肪酸组成的变化。结果表明:总氨基酸组成在受精卵和卵黄囊仔鱼之间变化明显,但是在卵黄囊仔鱼和开口仔鱼之间只有细微的变化。开口仔鱼与其摄食的轮虫的总必需氨基酸组成相关。受精卵、卵黄囊仔鱼、开口仔鱼的游离氨基酸含量分别为139 mg/g、3.6 mg/g和2.5 mg/g,占总氨基酸含量的22.3%、3.6%和2.5%。饱和脂肪酸的总量从受精卵到卵黄囊仔鱼明显下降,但是发育到开口仔鱼含量无显著变化。单不饱和脂肪酸和多不饱和脂肪酸的总量在不同发育阶段无显著变化,而EPA和DHA的含量从卵黄囊仔鱼到开口仔鱼有明显下降。这表明在早期发育阶段半滑舌鳎主要利用饱和脂肪酸作为能量代谢的基质,对饱和脂肪酸的利用程度大于单不饱和脂肪酸和多不饱和脂肪酸。半滑舌鳎似乎需要长链的多不饱和脂肪酸如EPA、DHA和ARA。