The isolation and characterisation of the wheat molecular ZIPper I homologue, TaZYP1

Extent: 13p.Background: The synaptonemal complex (SC) is a proteinaceous tripartite structure used to hold homologous chromosomes together during the early stages of meiosis. The yeast ZIP1 and its homologues in other species have previously been characterised as the transverse filament protein of the synaptonemal complex. Proper installation of ZYP1 along chromosomes has been shown to be dependent on the axial element-associated protein, ASY1 in Arabidopsis. Results: Here we report the isolation of the wheat (Triticum aestivum) ZYP1 (TaZYP1) and its expression profile (during and post-meiosis) in wild-type, the ph1b deletion mutant as well as in Taasy1 RNAi knock-down mutants. TaZYP1 has a putative DNA-binding S/TPXX motif in its C-terminal region and we provide evidence that TaZYP1 interacts non-preferentially with both single- and double-stranded DNA in vitro. 3-dimensional dual immunofluorescence localisation assays conducted with an antibody raised against TaZYP1 show that TaZYP1 interacts with chromatin during meiosis but does not co-localise to regions of chromatin where TaASY1 is present. The TaZYP1 signal lengthens into regions of chromatin where TaASY1 has been removed in wild-type but this appears delayed in the ph1b mutant. The localisation profile of TaZYP1 in four Taasy1 knock-down mutants is similar to wild-type but TaZYP1 signal intensity appears weaker and more diffused. Conclusions: In contrast to previous studies performed on plant species where ZYP1 signal is sandwiched by ASY1 signal located on both axial elements of the SC, data from the 3-dimensional dual immunofluorescence localisation assays conducted in this study show that TaZYP1 signal only lengthens into regions of chromatin after TaASY1 signal is being unloaded. However, the observation that TaZYP1 loading appears delayed in both the ph1b and Taasy1 mutants suggests that TaASY1 may still be essential for TaZYP1 to play a role in SC formation during meiosis. These data further suggest that the temporal installation of ZYP1 onto pairing homologous chromosomes in wheat is different to that of other plant species and highlights the need to study this synaptonemal complex protein on a species to species basis.Kelvin HP Khoo, Amanda J Able and Jason A Abl

Poor Homologous Synapsis 1 Interacts with Chromatin but Does Not Colocalise with ASYnapsis 1 during Early Meiosis in Bread Wheat

Chromosome pairing, synapsis, and DNA recombination are three key processes that occur during early meiosis. A previous study of Poor Homologous Synapsis 1 (PHS1) in maize suggested that PHS1 has a role in coordinating these three processes. Here we report the isolation of wheat (Triticum aestivum) PHS1 (TaPHS1), and its expression profile during and after meiosis. While the TaPHS1 protein has sequence similarity to other plant PHS1/PHS1-like proteins, it also possesses a unique region of oligopeptide repeat units. We show that TaPHS1 interacts with both single- and double-stranded DNA in vitro and provide evidence of the protein region that imparts the DNA-binding ability. Immunolocalisation data from assays conducted using antisera raised against TaPHS1 show that TaPHS1 associates with chromatin during early meiosis, with the signal persisting beyond chromosome synapsis. Furthermore, TaPHS1 does not appear to colocalise with the asynapsis protein (TaASY1) suggesting that these proteins are probably independently coordinated. Significantly, the data from the DNA-binding assays and 3-dimensional immunolocalisation of TaPHS1 during early meiosis indicates that TaPHS1 interacts with DNA, a function not previously observed in either the Arabidopsis or maize PHS1 homologues. As such, these results provide new insight into the function of PHS1 during early meiosis in bread wheat

Transitions in the morphological features, habitat use, and diet of young-of-the-year goosefish (Lophius americanus)

This study was designed to improve our understanding of transitions in the early life history and the distribution, habitat use, and diets for young-of-the-year (YOY) goosefish (Lophius americanus) and, as a result, their role in northeastern U.S. continental shelf ecosystems. Pelagic juveniles (>12 to ca. 50 mm total length [TL]) were distributed over most portions of the continental shelf in the Middle Atlantic Bight, Georges Bank, and into the Gulf of Maine. Most individuals settled by 50−85 mm TL and reached approximately 60−120 mm TL by one year of age. Pelagic YOY fed on chaetognaths, hyperiid amphipods, calanoid copepods, and ostracods, and benthic YOY had a varied diet of fishes and benthic crustaceans. Goosefish are widely scattered on the continental shelf in the Middle Atlantic Bight during their early life history and once settled, are habitat generalists, and thus play a role in many continental shelf habi

Characterisation of ethylene pathway components in non-climacteric capsicum

Background: Climacteric fruit exhibit high ethylene and respiration levels during ripening but these levels are limited in non-climacteric fruit. Even though capsicum is in the same family as the well-characterised climacteric tomato (Solanaceae), it is non-climacteric and does not ripen normally in response to ethylene or if harvested when mature green. However, ripening progresses normally in capsicum fruit when they are harvested during or after what is called the ‘Breaker stage’. Whether ethylene, and components of the ethylene pathway such as 1-aminocyclopropane 1-carboxylate (ACC) oxidase (ACO), ACC synthase (ACS) and the ethylene receptor (ETR), contribute to non-climacteric ripening in capsicum has not been studied in detail. To elucidate the behaviour of ethylene pathway components in capsicum during ripening, further analysis is therefore needed. The effects of ethylene or inhibitors of ethylene perception, such as 1-methylcyclopropene, on capsicum fruit ripening and the ethylene pathway components may also shed some light on the role of ethylene in non-climacteric ripening. Results: The expression of several isoforms of ACO, ACS and ETR were limited during capsicum ripening except one ACO isoform (CaACO4). ACS activity and ACC content were also low in capsicum despite the increase in ACO activity during the onset of ripening. Ethylene did not stimulate capsicum ripening but 1-methylcyclopropene treatment delayed the ripening of Breaker-harvested fruit. Some of the ACO, ACS and ETR isoforms were also differentially expressed upon treatment with ethylene or 1-methylcyclopropene. Conclusions: ACS activity may be the rate limiting step in the ethylene pathway of capsicum which restricts ACC content. The differential expression of several ethylene pathway components during ripening and upon ethylene or 1-methylclopropene treatment suggests that the ethylene pathway may be regulated differently in non-climacteric capsicum compared to the climacteric tomato. Ethylene independent pathways may also exist in non-climacteric ripening as evidenced by the up-regulation of CaACO4 during ripening onset despite being negatively regulated by ethylene exposure. However, some level of ethylene perception may still be needed to induce ripening especially during the Breaker stage. A model of capsicum ripening is also presented to illustrate the probable role of ethylene in this non-climacteric fruit.Wan M Aizat, Jason A Able, James CR Stangoulis and Amanda J Abl

Staff and student perceptions of assessment value and workload

BACKGROUND AND AIM As teachers, we aim to design valuable and authentic assessment which engages students purposefully enabling them to demonstrate learning outcomes appropriately. However, the style of assessment and extent of engagement required by the student may differ between subjects and is dependent upon factors such as year level and discipline. Engagement with and design of assessment is further impacted by workload of students and staff respectively. This project explored staff and student perceptions of assessment in the Faculty of Science, Engineering and Technology at the University of Adelaide, allowing the co-creation of guidelines for assessment design/practice. DESIGN AND METHODS Students completed surveys in-class (n=98) or online (n=51) with students also participating in 4 focus groups (n=25). Academics completed an online survey (n=34) with n=25 being interviewed. RESULTS AND DISCUSSION Regardless of discipline, students prefer to have multiple, and different types, of assessments with low weightings over a semester to enable formative feedback and to demonstrate their learning more easily. They acknowledged the impact on academic workload with most academics indicating that 4-5 assessments per subject were ideal over the semester. Students usually equated the weighting of tasks with the expected workload whereas many academics tended to weight assessment based on the importance of the learning outcomes. Most academics (56%) did not provide guidance to students about their expectations for required workload for individual assignments (at different grade levels). Final exams were seen by students as the least valuable type of assessment to demonstrate their attainment of learning outcomes. Interestingly, students acknowledged the academics’ viewpoint that final invigilated exams are essential (‘to stop cheating or plagiarism’) and suggested that there should be a hurdle on the final exam but that it be weighted less than 50%. Group assignments were also ranked as less valuable by students and academics. Students did not always see the relevance of working in a group (‘other than to reduce the workload of the academic’) and were often stressed about equal distribution of workload and/or the impact of relying on others for their grade. Academics acknowledged the need to improve how we teach groupwork skills and manage peer assessment. Students thought the most valuable assessments were low-weighting, online, open-book, weekly quizzes/tests with multiple choice questions (MCQs) because they were ‘for learning’, did not require as much time and were often designed by academics to require higher order learning (such as application and synthesis). Academics indicated that quizzes and mid-semester exams were valuable for reducing pressure of the final exam on students. However, the design and development of appropriate MCQs increased workloads because ‘you have to be clever’ and it ‘just takes too much time’. Practical reports and practical-based activities were also ranked as extremely valuable in the surveys by students and academics. However, focus group discussions with students suggested this was contingent on the relevance of the report or activity to a future role/career. In conclusion, students are often most concerned about fairness and consistency in assessment but also had a limited understanding of the rationale for assessment design and required input. Therefore, the co-created guidelines include a suggestion that academics provide detailed expectations (especially relating to workload) and information about the purpose of the assessment and its design

Salt Marsh Peat Dispersal: Habitat for Fishes, Decapod Crustaceans, and Bivalves

Salt marshes, especially those of Spartina alterniflora, are among the most productive habitats on Earth. The peat that is formed and accumulates there, as below-ground biomass, can be dispersed in a number of ways, through calving off the marsh edge along bays, in creeks, and other locations as occurs in the Mullica River – Great Bay estuary in southern New Jersey. Based on a variety of sampling approaches, including those collected by sidescan sonar and direct collection, we provide new insights into the ecological role of dispersed peat. Some of this is ice rafted on the marsh surface during storms. Elsewhere, and most commonly, it falls into the intertidal channels or flats where it may continue to support the growth of Spartina, and associated invertebrates such as Geukensia demissa. If it is deposited subtidally these may not be as likely, but in these situations the peat provides structured habitat for other animals such as fishes, crabs, shrimps, and bivalves

Seasonal distribution, abundance, and growth of young-of-the-year Atlantic croaker (Micropogonias undulatus) in Delaware Bay and adjacent marshes

We examined the spatial and temporal distribution, abundance, and growth of young-of-the-year (YOY) Atlantic croaker (Micropogonias undulatus) in Delaware Bay, one of the northernmost estuaries in which they consistently occur along the east coast of the United States. Sampling in Delaware Bay and in tidal creeks in salt marshes adjacent to the bay with otter trawls, plankton nets and weirs, between April and November 1996–99, collected approximately 85,000 YOY. Ingress of each year class into the bay and tidal creeks consistently occurred in the fall, and the first few YOY appeared in August. Larvae as small as 2–3 mm TL were collected in September and October 1996. Epibenthic individuals <25 mm TL were present each fall and again during spring of each year, but not in 1996 when low water temperatures in January and February apparently caused widespread mortality, resulting in their absence the following spring and summer. In 1998 and 1999, a second size class of smaller YOY entered the bay and tidal creeks in June. When YOY survived the winter, there was no evidence of growth until after April. Then the YOY grew rapidly through the summer in all habitats (0.8–1.4 mm/d from May through August). In the bay, they were most abundant from June to August over mud sediments in oligohaline waters. They were present in both subtidal and intertidal creeks in the marshes where they were most abundant from April to June in the mesohaline portion of the lower bay. The larger YOY began egressing out of the marshes in late summer, and the entire year class left the tidal creeks at lengths of 100–200 mm TL by October or November when the next year class was ingressing. These patterns of seasonal distribution and abundance in Delaware Bay and the adjacent marshes are similar to those observed in more southern estuaries along the east coast; however, growth is faster—in keeping with that in other northern estuaries

Movements and growth of tagged young-of-the-year Atlantic croaker (Micropogonias undulatus L.) in restored and reference marsh creeks in Delaware Bay, USA

Abstract The residence time, movements, and growth of tagged young-of-the-year Atlantic croaker, Micropogonias undulatus L., were studied from July to October 1998 as measures of the success of a marsh restoration project adjacent to Delaware Bay. A total of 8173 croaker (41 -121 mm SL) were tagged from each of two creeks in both marshes during July and August with internal sequential coded wire microtags. A prior tag-retention study in the laboratory found a 95% tag retention rate. Of those tagged, 3.6% were recaptured within and nearby the study creeks using seines, otter trawls, and weirs during a 105-day period. Recapture percentages ranged from 1.5% to 6.1% in individual creeks in the restored marsh. There was some movement of tagged fish between creeks in the restored marsh and out into the main creek, but 95% of the recaptures were made in the subtidal and intertidal portions of the same creek in which they were tagged. Fewer fish were recaptured at the reference marsh (1.6% recapture; n = 1489 tagged) up to 50 days after tagging, with no evidence of movement between creeks. The average individual growth rates for recaptured croaker was the same in both restored (0.69 mm/day) and reference (0.63 mm/day) marshes before egress from the creeks in September and October. As a result, both created creeks in a restored marsh and natural creeks in a reference marsh appeared to be utilized as young-of-the-year habitat in a similar way during the summer and until egress out the marshes during the fall, thus this restoration effort has been successful in creating suitable habitat for Atlantic croaker.

Loss of DBC1 (CCAR2) affects TNFα-induced lipolysis and Glut4 gene expression in murine adipocytes

© 2018 Society for Endocrinology Published by Bioscientifica Ltd. STAT5A (signal transducer and activator of transcription 5A) is a transcription factor that plays a role in adipocyte development and function. In this study, we report DBC1 (deleted in breast cancer 1 - also known as CCAR2) as a novel STAT5A-interacting protein. DBC1 has been primarily studied in tumor cells, but there is evidence that loss of this protein may promote metabolic health in mice. Currently, the functions of DBC1 in mature adipocytes are largely unknown. Using immunoprecipitation and immunoblotting techniques, we confirmed that there is an association between endogenous STAT5A and DBC1 proteins under physiological conditions in the adipocyte nucleus that is not dependent upon STAT5A tyrosine phosphorylation. We used siRNA to knockdown DBC1 in 3T3-L1 adipocytes to determine the impact on STAT5A activity, adipocyte gene expression and TNFα (tumor necrosis factor α)-regulated lipolysis. The loss of DBC1 did not affect the expression of several STAT5A target genes including Socs3, Cish, Bcl6, Socs2 and Igf1. However, we did observe decreased levels of TNFα-induced glycerol and free fatty acids released from adipocytes with reduced DBC1 expression. In addition, DBC1-knockdown adipocytes had increased Glut4 expression. In summary, DBC1 can associate with STAT5A in adipocyte nucleus, but it does not appear to impact regulation of STAT5A target genes. Loss of adipocyte DBC1 modestly increases Glut4 gene expression and reduces TNFα-induced lipolysis. These observations are consistent with in vivo observations that show loss of DBC1 promotes metabolic health in mice

Resource use among patients with diabetes, diabetic neuropathy, or diabetes with depression

BACKGROUND: Diabetes is often associated with complications and comorbidities. The purpose of this research is to compare medical resources used by patients with the following diagnoses: diabetes mellitus (DM), diabetic neuropathy (DN), and diabetes mellitus combined with comorbid depression (DD). METHODS: Adult patients who were diagnosed with DM, DN, or DD were included in the study. There were 55,972 patients in the DM cohort, 2,146 in the DN, and 2,379 in the DD. P values for comparisons between the three mutually exclusive cohorts were conducted using the Tukey-Kramer method. Cost comparisons among the cohorts were conducted using a stepwise multivariate regression that controlled for patient characteristics and comorbid conditions. RESULTS: Individuals in the DM or DN cohorts were generally more likely to use antidiabetic medications than patients in the DD group. Those diagnosed with DN or DD generally used more pain medications than individuals in the DM cohort. The DM cohort had significantly lower diabetes-related total medical costs ($1,297 v$5,125, p < 0.0001) and lower total medical costs ($4,819 v$24,765, p < 0.0001) than the DN cohort. The DM cohort also had significantly lower diabetes-related total medical costs ($1,297 v$3,264, p < 0.0001) as well as significantly lower total medical costs ($4,819 v$19,298, p < 0.0001) than the DD cohort. CONCLUSION: Results from this study indicated significant differences in demographic characteristics, comorbidities, and medication use among individuals diagnosed with DM, DN, or DD. These differences translated into significant cost differences. Patients diagnosed with DN or DD had higher diabetes-related costs than patients diagnosed with DM