Transgenerational plasticity and climate change experiments: Where do we go from here?

Phenotypic plasticity, both within and across generations, is an important mechanism that organisms use to cope with rapid climate change. While an increasing number of studies show that plasticity across generations (transgenerational plasticity or TGP) may occur, we have limited understanding of key aspects of TGP, such as the environmental conditions that may promote it, its relationship to within‐generation plasticity (WGP) and its role in evolutionary potential. In this review, we consider how the detection of TGP in climate change experiments is affected by the predictability of environmental variation, as well as the timing and magnitude of environmental change cues applied. We also discuss the need to design experiments that are able to distinguish TGP from selection and TGP from WGP in multigenerational experiments. We conclude by suggesting future research directions that build on the knowledge to date and admit the limitations that exist, which will depend on the way environmental change is simulated and the type of experimental design used. Such an approach will open up this burgeoning area of research to a wider variety of organisms and allow better predictive capacity of the role of TGP in the response of organisms to future climate change.     

The ecological integrity of the lower Olifants River,Limpopo province,South Africa: 2009–2015 – Part B: Tributaries of the Olifants River

Monitoring on the Lowveld reaches of the Olifants River, Limpopo River System, and its Steelpoort, Blyde, Klaserie and Selati tributaries was initiated in 2009. Analysis of the 2009–2015 data from four Olifants River sites showed deterioration in the river’s ecological condition between where it enters the Lowveld and where it enters the Kruger National Park, with a slight recovery within the Kruger National Park. Physico-chemical, aquatic macroinvertebrate and fish data collected in 2009–2015 at six sites on the Steelpoort, Blyde, Klaserie and Selati tributaries of the Olifants River corroborated the ecological condition of these tributaries. The Selati was the most polluted and was in a critically modified condition, whereas the Klaserie and Steelpoort were in fair condition and the Blyde was in good condition. The Selati appeared to have a significant negative impact on the water quality, macroinvertebrates and fish of the Olifants River within the Kruger National Park.     

Human health risks of metals and metalloids in muscle tissue of Synodontis zambezensis Peters, 1852 from Flag Boshielo Dam,South Africa

Muscle tissue from 63 Synodontis zambezensis collected bimonthly in 2013 at Flag Boshielo Dam were analysed for metals and metalloids in a desktop human health risk assessment. The Hazard Quotient, based on a weekly meal of 67 g of fish muscle, exceeded the maximum acceptable level of one for lead, cobalt, cadmium, mercury, arsenic and selenium. The concentrations of these elements were higher in 2013 than those recorded in 2009 and 2012 in other fish species from Flag Boshielo Dam and these may pose a long-term health risk if consumed regularly by impoverished rural communities reliant on fish as a source of protein.     

Assessing Risks of Plant-Based Pharmaceuticals: I. Human Dietary Exposure

Protein-based drugs are the fastest growing class of drugs for the treatment of disease in humans and other animals. However, the current method of producing proteins for pharmaceutical application is predicted to fall short because of population growth and demographic trends. This study characterized human dietary risks using quantitative risk assessment techniques for three pharmaceutical proteins produced in field-grown maize. The three proteins were aprotinin, gastric lipase, and Escherichia coli heat-labile enterotoxin B subunit (LT-B). The human dietary risks from the three proteins inadvertently occurring in food were evaluated using three different exposure scenarios so that potential risks could be compared. The three exposure scenarios ranged in conservatism to evaluate the range of risk between the proteins and scenarios. Risk quotients (RQs) were calculated for all three scenarios to integrate exposure and effect (toxicity). The risk assessments revealed that the most conservative scenario produced higher RQs than the other two scenarios. The dietary risks from scenario 1 for aprotinin were three orders of magnitude greater than for scenario 2, and four orders of magnitude greater than for scenario 3. This risk assessment revealed that dietary risks will vary dramatically and depend on factors such as the specific pharmaceutical protein, protein expression, and exposure scenarios. The assessment also reinforced the need for case-by-case assessments.     

Differential effects of p63 mutants on transactivation of p53 and/or p63 responsive genes

p63, known to play a role in development, has more recently also been implicated in cancer progression. Mutations in p63 have been shown to be responsible for several human developmental diseases. Differential splicing of the p63 gene gives rise to p63 isoforms, which can act either as tumor suppressors or as oncogene. In this report, we studied the effects of naturally occurring TAp637 mutants on the regulation of p53/p63 and p63 specific target genes. We observed significant differences among p63 mutants to regulate the p53/p63 and p63 specific target genes. Additionally, we observed a differential effect of p63 mutants on wildtype-p63-mediated induction ofp53/p63 and p63 specific target genes. We also demonstrated that these mutants differentially regulate the binding of wildtype p63 to the promoter of target genes. Furthermore, the effects of these mutants on cell death and survival were consistent with their ability to regulate the downstream targets when compared to wildtype TAp63T. In summary, our data demonstrate that p63 mutants exhibit differential effects on p63 and p53/p63 specific target genes and on the induction of apoptosis, and provide further insight into the function of p63.     

Ten polymorphic microsatellite loci isolated from the alpine caddisfly Allogamus uncatus Brauer (Trichoptera: Limnephilidae)

Here we report the development of 10 microsatellite loci for the alpine caddisfly, Allogamus uncatus. Polymorphism as detected in 24 individuals ranged from three to 17 alleles per locus, and observed heterozygosity ranged from 0.087 to 0.864. These primers will enable research on the genetic population structure of this species, the extent of gene flow among alpine permanent and temporary streams, and the genetic consequences of extinction/recolonization events.     

Sequential abundant ion fragmentation analysis (SAIFA): an alternative approach for phosphopeptide identification using an ion trap mass spectrometer

Phosphorylation has been the most studied of all the posttranslational modifications of proteins. Mass spectrometry has emerged as a powerful tool for phosphomapping on proteins/peptides. Collision-induced dissociation (CID) of phosphopeptides leads to the loss of phosphoric or metaphosphoric acid as a neutral molecule, giving an intense neutral loss product ion in the mass spectrum. Dissociation of the neutral loss product ion identifies peptide sequence. This method of data-dependent constant neutral loss (DDNL) scanning analysis has been commonly used for mapping phosphopeptides. However, preferential losses of groups other than phosphate are frequently observed during CID of phosphopeptides. Ions that result from such losses are not identified during DDNL analysis due to predetermined scanning for phosphate loss. In this study, we describe an alternative approach for improved identification of phosphopeptides by sequential abundant ion fragmentation analysis (SAIFA). In this approach, there is no predetermined neutral loss molecule, thereby undergoing sequential fragmentation of abundant peak, irrespective of the moiety lost during CID. In addition to improved phosphomapping, the method increases the sequence coverage of the proteins identified, thereby increasing the confidence of protein identification. To the best of our knowledge, this is the first report to use SAIFA for phosphopeptide identification.     

Assessment of pharmacological activities of two medicinal plant of Bangladesh: Launaea sarmentosa and Aegialitis rotundifolia roxb in the management of pain,pyrexia and inflammation

Background

The current study aims at evaluating the analgesic, anti-pyretic and anti-inflammatory properties of methanolic extract of the stem, bark and leaves of Launaea sarmentosa and Aegialitis rotundifolia roxb.

Results

The AELS and AEAR extract presented a significant (***p < 0.001) dose dependent increase in reaction time in writhing method and showed inhibition of 63.1% and 57.1% respectively at the doses of 400 mg/kg body weight while standard drug showed (P < 0.001) inhibition of 69.23%. In tail immersion method, AELS and AEAR showed maximum time of tail retention at 30 min in hot water i.e. 6.93 sec and 6.54 sec respectively at highest doses of 400 mg/kg body weight than lower dose while standard pentazocine showed reaction time of 7.62 sec. The AELS and AEAR extract also exhibited promising anti-inflammatory effect as demonstrated by statistically significant inhibition of paw volume by 32.48% and 26.75% respectively at the dose of 400 mg/kg body weight while the value at the dose of 200 mg/kg body weight were linear to higher dose at the 3^rd hour of study. On the other hand, Standard indomethacin inhibited 40.13% of inflammation (***P < 0.001). In Cotton-pellet granuloma method, AELS and AEAR extract at the dose of 400 mg/kg body weight exhibited inhibition of inflammation of 34.7% and 29.1% respectively while standard drug showed (P < 0.001) inhibition of 63.22%. Intraperitoneal administration of AELS and AEAR showed dose dependent decrease in body temperature in brewer’s yeast induced hyperthermia in rats at both doses. However, AELS significantly decreased body temperature (***p < 0.001) at 400 mg/kg compared to control.

Conclusions

Present work propose that the methanolic extract of Launaea sarmentosa and Aegialitis rotundifolia roxb possesses dose dependent pharmacological action which supports its therapeutic use in folk medicine possibly mediated through the inhibition or blocking of release of prostaglandin and/or actions of vasoactive substances such as histamine, serotonin and kinins.     

Grandparental effects in marine sticklebacks: transgenerational plasticity across multiple generations

Nongenetic inheritance mechanisms such as transgenerational plasticity (TGP) can buffer populations against rapid environmental change such as ocean warming. Yet, little is known about how long these effects persist and whether they are cumulative over generations. Here, we tested for adaptive TGP in response to simulated ocean warming across parental and grandparental generations of marine sticklebacks. Grandparents were acclimated for two months during reproductive conditioning, whereas parents experienced developmental acclimation, allowing us to compare the fitness consequences of short‐term vs. prolonged exposure to elevated temperature across multiple generations. We found that reproductive output of F1 adults was primarily determined by maternal developmental temperature, but carry‐over effects from grandparental acclimation environments resulted in cumulative negative effects of elevated temperature on hatching success. In very early stages of growth, F2 offspring reached larger sizes in their respective paternal and grandparental environment down the paternal line, suggesting that other factors than just the paternal genome may be transferred between generations. In later growth stages, maternal and maternal granddam environments strongly influenced offspring body size, but in opposing directions, indicating that the mechanism(s) underlying the transfer of environmental information may have differed between acute and developmental acclimation experienced by the two generations. Taken together, our results suggest that the fitness consequences of parental and grandparental TGP are highly context dependent, but will play an important role in mediating some of the impacts of rapid climate change in this system.     

Effects of double ligation of Stensen's duct on the rabbit parotid gland

Salivary gland duct ligation is an alternative to gland excision for treating sialorrhea or reducing salivary gland size prior to tumor excision. Duct ligation also is used as an approach to study salivary gland aging, regeneration, radiotherapy, sialolithiasis and sialadenitis. Reports conflict about the contribution of each salivary cell population to gland size reduction after ductal ligation. Certain cell populations, especially acini, reportedly undergo atrophy, apoptosis and proliferation during reduction of gland size. Acini also have been reported to de-differentiate into ducts. These contradictory results have been attributed to different animal or salivary gland models, or to methods of ligation. We report here a bilateral double ligature technique for rabbit parotid glands with histologic observations at 1, 7, 14, 30, 60 days after ligation. A large battery of special stains and immunohistochemical procedures was employed to define the cell populations. Four stages with overlapping features were observed that led to progressive shutdown of gland activities: 1) marked atrophy of the acinar cells occurred by 14 days, 2) response to and removal of the secretory material trapped in the acinar and ductal lumens mainly between 30 and 60 days, 3) reduction in the number of parenchymal (mostly acinar) cells by apoptosis that occurred mainly between 14–30 days, and 4) maintenance of steady-state at 60 days with a low rate of fluid, protein, and glycoprotein secretion, which greatly decreased the number of leukocytes engaged in the removal of the luminal contents. The main post- ligation characteristics were dilation of ductal and acinar lumens, massive transient infiltration of mostly heterophils (rabbit polymorphonuclear leukocytes), acinar atrophy, and apoptosis of both acinar and ductal cells. Proliferation was uncommon except in the larger ducts. By 30 days, the distribution of myoepithelial cells had spread from exclusively investing the intercalated ducts pre-ligation to surrounding a majority of the residual duct-like structures, many of which clearly were atrophic acini. Thus, both atrophy and apoptosis made major contributions to the post-ligation reduction in gland size. Structures also occurred with both ductal and acinar markers that suggested acini differentiating into ducts. Overall, the reaction to duct ligation proceeded at a considerably slower pace in the rabbit parotid glands than has been reported for the salivary glands of the rat.