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Food-induced morphological plasticity, a type of developmental plasticity, is a well-documented phenomenon in larvae of the echinoid echinoderm, Dendraster excentricus A recent study in our lab has shown that this morphological plasticity is associated with significant physiological plasticity for growth. The goal of the current study was to measure several aspects of protein metabolism in larvae growing at different rates to understand the mechanistic basis for this physiological growth plasticity. Larvae of D. excentricus were fed rations of 1000 algal cells ml -1 (low-fed larvae) or 10,000 algal cells ml -1 (high-fed larvae). Relative protein growth rate was 6.0 and 12.2% day -1 for low- and high-fed larvae, respectively. The energetic cost of protein synthesis was similar for the two treatments at 4.91 J mg -1 protein synthesized. Larvae in both treatments used about 50% of their metabolic energy production to fuel protein synthesis. Mass-specific rates of protein synthesis were also similar. Large differences in mass-specific rates of protein degradation were observed. Low-fed larvae had relatively low rates of degradation early in development that increased with larval age, surpassing those of high-fed larvae at 20 days post-fertilization. Changes in protein depositional efficiency during development were similar to those of larval growth efficiency, indicating that differences in protein metabolism are largely responsible for whole-organism growth plasticity. Low-fed larvae also had alanine transport rates that were 2 times higher than those of high-fed larvae. In total, these results provide an explanation for the differences in growth efficiency between low- and high-fed larvae and allow for a more integrated understanding of developmental plasticity in echinoid larvae., Competing Interests: Competing interestsThe authors declare no competing or financial interests. Author contributionsConceptualization: D.A.P.; Methodology: A.E., D.A.P.; Validation: D.A.P.; Formal analysis: A.E., A.K.P., D.A.P.; Investigation: A.E., A.K.P.; Resources: D.A.P.; Data curation: A.E.; Writing - original draft: A.E., D.A.P.; Writing - review & editing: A.E., A.K.P., D.A.P.; Supervision: D.A.P.; Project administration: D.A.P.; Funding acquisition: D.A.P., (© 2021. Published by The Company of Biologists Ltd.)

High-throughput sequencing has enabled many powerful approaches in biological research. Here, we review sequencing approaches to measure frequency changes within engineered mutational libraries subject to selection. These analyses can provide direct estimates of biochemical and fitness effects for all individual mutations across entire genes (and likely compact genomes in the near future) in genetically tractable systems such as microbes, viruses, and mammalian cells. The effects of mutations on experimental fitness can be assessed using sequencing to monitor time-dependent changes in mutant frequency during bulk competitions. The impact of mutations on biochemical functions can be determined using reporters or other means of separating variants based on individual activities (e.g., binding affinity for a partner molecule can be interrogated using surface display of libraries of mutant proteins and isolation of bound and unbound populations). The comprehensive investigation of mutant effects on both biochemical function and experimental fitness provide promising new avenues to investigate the connections between biochemistry, cell physiology, and evolution. We summarize recent findings from systematic mutational analyses; describe how they relate to a field rich in both theory and experimentation; and highlight how they may contribute to ongoing and future research into protein structure-function relationships, systems-level descriptions of cell physiology, and population-genetic inferences on the relative contributions of selection and drift., (Copyright © 2014 by the Genetics Society of America.)

Background: Mutations in C9ORF72 are an important cause of frontotemporal dementia (FTD) and motor neuron disease. Accumulating evidence suggests that FTD associated with C9ORF72 mutations (C9ORF72-FTD) is distinguished clinically by early prominent neuropsychiatric features that might collectively reflect deranged body schema processing. However, the pathophysiology of C9ORF72-FTD has not been elucidated., Methods: We undertook a detailed neurophysiological investigation of five patients with C9ORF72-FTD, in relation to patients with FTD occurring sporadically and on the basis of mutations in the microtubule-associated protein tau gene and healthy older individuals. We designed or adapted behavioural tasks systematically to assess aspects of somatosensory body schema processing (tactile discrimination, proprioceptive and body part illusions and self/non-self differentiation)., Results: Patients with C9ORF72-FTD selectively exhibited deficits at these levels of body schema processing in relation to healthy individuals and other patients with FTD., Conclusions: Altered body schema processing is a novel, generic pathophysiological mechanism that may link the distributed cortico-subcortical network previously implicated in C9ORF72-FTD with a wide range of neuropsychiatric and behavioural symptoms, and constitute a physiological marker of this neurodegenerative proteinopathy., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

The successful analysis of physiological processes requires quantitative understanding of the functional interactions between the key components of cells, organs and systems, and how these interactions change in disease states. This information does not reside in the genome, or even in the individual proteins that genes code for. There is therefore no alternative to copying nature and computing these interactions to determine the logic of healthy and diseased states. The rapid growth in biological databases, models of cells, tissues and organs, and in computing power has made it possible to explore functionality all the way from the level of genes to whole organs and systems. Examples are given of genetic modifications of the Na+ channel protein in the heart that predispose people to ventricular fibrillation, and of multiple target therapy in drug development. Complexity in biological systems also arises from tissue and organ geometry. This is illustrated using modelling of the whole heart.

Ovarian hyperandrogenism can be associated with insulin resistance, hyperinsulinemia, glucose intolerance, and obesity. High levels of the lipostatic hormone, leptin, have also been reported in this condition. The purpose of the present study was to examine the effect of an oral contraceptive (OC) of low androgenicity containing desogestrel on glucose tolerance in hyperandrogenic women and the impact of changes in androgenic/estrogenic status on leptin concentrations. Sixteen nondiabetic hyperandrogenic women, aged 29 +/- 1 yr with a body mass index (BMI) of 36.8 +/- 1.8 kg/m2, underwent an oral glucose tolerance test before and after 6 months of therapy with the OC. Free testosterone decreased and sex hormone-binding globulin increased after therapy (P < 0.001). Glucose tolerance deteriorated significantly, and two women developed diabetes. Body weight, BMI, and leptin did not change significantly. Leptin correlated with BMI before (r = 0.56; P = 0.02) and after (r = 0.51; P = 0.04) treatment, but not with glucose, insulin, total and free testosterone, or sex hormone-binding globulin before or after treatment. In conclusion, 1) glucose tolerance should be monitored in hyperandrogenic women using OC, even those of low androgenicity; and 2) changes in androgenic/estrogenic status had no effect on the leptin concentration, suggesting that its sexual dimorphism is not related to sex steroids.

Fluids were collected from the proximal vas deferens of 18 normal fertile men and 32 vasectomized men during vasectomy or vasovasostomy, respectively, and the protein concentration and pattern of proteins were then analysed by sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE). In normal fertile men and vasectomized men there were no significant differences in total protein concentrations between fluids from the left and right vas deferens. The total protein concentration of proximal vas fluid from vasectomized men (82.8 +/- 7.5 mg/ml; mean +/- SEM) was significantly higher than in normal fertile men (36.8 +/- 4.5 mg/ml). In vasectomized men there was no significant correlation between the total protein concentration in vas fluid and the duration of vasectomy. The patterns of protein bands in proximal vas fluid differed from those in seminal plasma. There was no relationship between the pattern of protein bands in vas fluid and the duration of vasectomy. Five major groups of proteins from proximal vas fluid were identified and no new major proteins were found in proximal vas fluid were identified and no new major proteins were found in proximal vas fluid after vasectomy. The percentage of 80K and 67K protein bands in vasectomized men was higher than that in normal fertile men. It is suggested that, after vasectomy, the physiological environment of the proximal vas deferens may be changed. One of these changes may be the higher total protein concentration (especially the 80K and 67K proteins) in vas fluid.

The albumin, immunoglobulin G (IgG), immunoglobulin A (IgA), lysozyme, lactoferrin, alpha 1-antitrypsin, alpha 1x-antichymotrypsin, and neutral proteinase levels of uterine fluid and serum of IUD-bearing women were studied in relationship to the phase of the menstrual cycle, the length of IUD implantation and the presence of reported side effects. Selection of these proteins was based on their potential importance in IUD-induced contraceptive action and/or side effects. Generally, only small differences were found in the serum levels of these proteins during the cycle, with different length of implantation or between patients with and without side effects. However, transudation of proteins (albumin, IgG, alpha 1-antitrypsin, alpha 1x-antichymotrypsin) from blood into the uterine cavity was enhanced by the IUD, especially during the postmenstrual and premenstrual periods. The IUD enhanced the local secretory response even more, i.e., the increased release of proteins from the endometrium (lysozyme, neutral proteinase, IgA) and from leukocytes (lysozyme, lactoferrin). Protein changes occurred as the period of insertion increased. These changes in the uterine milieu may account in part for the contraceptive action of the IUD. The secretory proteins rather than the transudation products differed between patients who showed IUD-associated side effects vs. those who did not, implying that IUD-related pathology is primarily associated with changes in local secretory response. The possible role of each protein in the mechanism of IUD action is presented in view of the present findings.

The proteins in human seminal plasma were mapped by high-resolution two-dimensional electrophoresis (ISO-DALT and BASO-DALT systems). When analyzed under dissociating conditions, samples from normal fertile males revealed a pattern of over 200 proteins, ranging in mass from 10 000 to 100 000 daltons. Comparison of the mapped proteins from these males and those who had undergone vasectomy allowed us to identify one series of glycoproteins as missing from the semen from vasectomized individuals. Glycoproteins isolated by affinity chromatography with use of concanavalin A were also mapped. Some of the protein spots were identified either by co-electrophoresis with purified proteins or by the electrophoretic transfer of proteins to nitrocellulose sheets and subsequent detection by immunological procedures. The proteins identified include a number of serum proteins as well as prostatic acid phosphatase and creatine kinase. Proteolytic events shown to occur during the liquefaction of semen that occurs early after collection indicate the importance of carefully controlled collection and preparation methods for clinical evaluation of seminal plasma. Ethylenediaminetetraacetic acid and phenylmethylsulfonyl fluoride inhibit this proteolysis.

The concentration of serum histidine-rich glycoprotein (HRG) was determined by radial immunodiffusion during weeks 27-42 of pregnancy in 110 pregnant women. HRG was also measured in serum from 11 lactating women 6 weeks post partum, from 11 women taking oral contraceptives, and from four women having progestin-releasing subcutaneous capsules used for contraception. The concentration of serum HRG decreased during the last trimester of pregnancy reaching a nadir at the 36-37th week (HRG 49 +/- 14 g/l, mean +/- SD). Thereafter serum HRG increased slightly towards term. In pregnancies complicated by hypertension the concentration of HRG was lower than in normal pregnancies at 32 weeks of pregnancy, but in other pathological pregnancies the values fell within the normal range. By 6 weeks postpartum normal non-pregnant HRG levels had been reached (107 +/- 13 g/l). The concentration of serum HRG was significantly lower in oral contraceptive users (74 +/- 22 g/l) than in controls (109 +/- 25 g/l, P less than 0.005). Low dose progestin treatment had no effect on serum HRG. The results show that serum HRG decreases during pregnancy and with oral contraceptive treatment and suggest that oestrogens are responsible for this increase.

Determinations by immunologic methods of histidine-rich glycoprotein (HRG) and plasminogen, were made in plasma samples collected during one normal or hormone induced cycle in 15 young, normal women and in 11 women using oral contraceptives with 30 micrograms ethinyl estradiol and 150 micrograms levo-norgestrel. The hormone group showed an increase in plasminogen level to about 150% of normal, while the concentration of HRG was decreased to about 75% of normal. This resulted in a considerable relative increase in the concentration of free plasminogen in the hormone group (calculated from the equilibrium: HRG . plasminogen in equilibrium HRG + plasminogen, using KD = 1.0 microM), representing a doubling of that in the normal group. Hence, more plasminogen is available for binding to fibrin and activation in the hormone group.

Progesterone has important effects on carbohydrate, lipid and protein metabolism. This steroid induces hyperinsulinemia, possibly by direct action on pancreatic islets, while promoting glycogen storage in the liver. Paradoxically, it antagonizes the effects of insulin on glucose metabolism in adipose tissue and skeletal muscle. Progesterone stimulates deposition of body fat but had catabolic effects on protein metabolism. Provisional evidence is offered that the steroid may influence ketone body production by the liver as well. When these steroid actions are considered together, their most relevant expression appears to be the physiologic changes observed during normal pregnancy.

Inhibin concentrations were measured in 109 seminal plasma samples obtained from 32 normal subjects, 51 infertile patients with either azoospermia or oligospermia, and 20 patients 2-8 months post vasectomy. The infertile group included 14 azoospermic patients with raised peripheral plasma FSH levels (6.8-30.2 IU/liter) and 17 azoospermic patients in whom FSH levels were normal. Only 6 of the 20 patients with oligospermia had raised FSH levels. Seminal plasma inhibin was measured in individual samples using a quantitative in vitro rat anterior pituitary cell culture bioassay in which FSH cell anterior pituitary cell culture bioassay in which FSH cell content was measured after 72 h of incubation with the inhibin-containing material. Biopotencies were determined using combined multiple parallel line assays with reference to an inhibin standard with a potency of 1 U/mg. The concentrations of inhibin in normal seminal plasma were 31.4 +/- 3.0 U/ml, which contrasted with the low levels found in azoospermic patients with high plasma FSH levels. Of these, seven had undetectable inhibin levels (less than 2.5 U/ml) and seven had values ranging from 4.2-8.5 U/ml. These concentrations were significantly lower than those in azoospermic patients, in whom FSH was not raised (18.9 +/- 2.2 U/ml). Seminal plasma inhibin levels post vasectomy were 16.9 +/- 2.3 U/ml and were not significantly different from those measured in azoospermic-normal FSH patients. Peripheral plasma FSH levels were expressed as a function of seminal plasma inhibin concentrations (r = -0.736; P less than 0.001; excluding those patients with vasal obstruction). These findings show that inhibin-like activity in seminal plasma is reduced in infertile men with raised peripheral plasma FSH levels, and that a reciprocal inverse relationship exists between serum FSH and seminal plasma inhibin concentrations.

Inhibin can exist in multiple forms. The size heterogeneity of inhibin (low and high molecular weight) is likely to be due to the purification procedures employed. However, irrespective of their size, both inhibin preparations are capable of suppressing circulating FSH levels. Since inhibin is a native hormone, the toxic effects after therapeutic administration are expected to be minimal. Inhibin is able to suppress only 70%-80% of the FSH secretion. Inhibin and the steroid (estrogen or androgen) may be involved in the physiological regulation of FSH. To completely suppress circulating FSH, administration of either a combination of inhibin and a steroid or a potent synthetic analogue of inhibin may be necessary. Inhibin has a very short half life in the adult animal, which may be due to the involvement of other testicular factors. Identification and characterization of these factors may help in prolonging effectiveness of inhibin.

Histidine-rich glycoprotein (HRG), a 3.8 S-alpha 2-glycoprotein recently identified as a new fibrinolysis regulating protein, was determined by an electroimmunoassay in samples of plasma collected during one menstrual or hormone cycle in 15 young women and in 11 women using oral contraceptives with 30 micrograms ethinyl oestradiol and 150 micrograms levo-norgestrel. Distinct individual levels caused the within-group variations of plasma HRG to be larger than the individual variations. In the hormone group the plasma HRG levels were decreased to about 75% of the normal, while the fluctuations during the cycle were minor in both groups.

When purified human globin is injected intravenously into rats it produces acute renal failure characterized by tubular casts and oliguria. The globin is identifiable within vesicles and channels in the cytoplasm of the proximal tubules, through which it passes from lumen to basal side with no apparent serious effect on the cells. When a very minimal amount of globin is taken up by cells of the distal limb of Henle's loop or distal tubules (lower nephron), a markedly deleterious effect is apparent and the cells die within a short time. The mixture of cell debris and precipitated globin forms plugs within the confines of the basement membranes of the former distal limbs and distal tubules. After a number of lower nephrons are plugged a disruption of proximal tubules is found, which apparently results from the effect of back pressure in the obstructed nephrons. We suggest that any amount in excess of a low threshold of globin, either alone or combined with heme or related material, has a toxic effect on lower nephron cells. Once initiated, the toxic effect is not reversible and the resulting plug of debris and precipitate will occlude the lumen. If a sufficient number of nephrons are made non-functional the animal becomes anuric; otherwise it is oliguric. A high rate of urine flow will protect against the excess absorption of material and thus against acute renal failure.