4 research outputs found
Perceptions of an assessment literacy module to improve academic judgement – a pilot study
Expectation differences between assessors and students regarding assignment marking often results in student dissatisfaction accompanied by student complaints, indicating that despite following assignment task briefs and marking criteria, students’ desired grades were not achieved. The Assessment Literacy Module (ALM) is an online grading tool designed to promote student development of evaluative judgement. The ALM allows evaluation of sample assignments – with students being the assessor – guided by assignment marking standards that convey how assessment criteria relate to the assignment outcome; a process that often highlights discrepancies in student academic judgement. Our pilot study surveyed staff (N = 13) and students (N = 105) to gauge perceptions of the impact of the ALM on the student learning experience. Students from eight subjects in Bioscience, Science and Biomedicine, across all three undergraduate levels, indicated that they now have a better understanding of their assessment criteria (85.7%), that they found the ALM helpful in preparing their assignments (87.6%), and that they are more confident with their assessment quality (78.1%). Staff indicated that they perceived students were able to use the feedback comments on the sample assignments to better understand assignment rubrics (69.2%), and that students who used the ALM had better comprehension of assessment expectations (84.6%)
Genome-Wide Screen for New Components of the Drosophila melanogaster Torso Receptor Tyrosine Kinase Pathway
Patterning of the Drosophila embryonic termini by the Torso (Tor) receptor pathway has long served as a valuable paradigm for understanding how receptor tyrosine kinase signaling is controlled. However, the mechanisms that underpin the control of Tor signaling remain to be fully understood. In particular, it is unclear how the Perforin-like protein Torso-like (Tsl) localizes Tor activity to the embryonic termini. To shed light on this, together with other aspects of Tor pathway function, we conducted a genome-wide screen to identify new pathway components that operate downstream of Tsl. Using a set of molecularly defined chromosomal deficiencies, we screened for suppressors of ligand-dependent Tor signaling induced by unrestricted Tsl expression. This approach yielded 59 genomic suppressor regions, 11 of which we mapped to the causative gene, and a further 29 that were mapped to <15 genes. Of the identified genes, six represent previously unknown regulators of embryonic Tor signaling. These include twins (tws), which encodes an integral subunit of the protein phosphatase 2A complex, and α-tubulin at 84B (αTub84B), a major constituent of the microtubule network, suggesting that these may play an important part in terminal patterning. Together, these data comprise a valuable resource for the discovery of new Tor pathway components. Many of these may also be required for other roles of Tor in development, such as in the larval prothoracic gland where Tor signaling controls the initiation of metamorphosis
Torso-like functions independently of Torso to regulate Drosophila growth and developmental timing
Activation of the Drosophila receptor tyrosine kinase Torso (Tor) only at the termini of the embryo is achieved by the localized expression of the maternal gene Torso-like (Tsl). Tor has a second function in the prothoracic gland as the receptor for prothoracicotropic hormone (PTTH) that initiates metamorphosis. Consistent with the function of Tor in this tissue, Tsl also localizes to the prothoracic gland and influences developmental timing. Despite these commonalities, in our studies of Tsl we unexpectedly found that tsl and tor have opposing effects on body size; tsl null mutants are smaller than normal, rather than larger as would be expected if the PTTH/Tor pathway was disrupted. We further found that whereas both genes regulate developmental timing, tsl does so independently of tor. Although tsl null mutants exhibit a similar length delay in time to pupariation to tor mutants, in tsl:tor double mutants this delay is strikingly enhanced. Thus, loss of tsl is additive rather than epistatic to loss of tor. We also find that phenotypes generated by ectopic PTTH expression are independent of tsl. Finally, we show that a modified form of tsl that can rescue developmental timing cannot rescue terminal patterning, indicating that Tsl can function via distinct mechanisms in different contexts. We conclude that Tsl is not just a specialized cue for Torso signaling but also acts independently of PTTH/Tor in the control of body size and the timing of developmental progression. These data highlight surprisingly diverse developmental functions for this sole Drosophila member of the perforin-like superfamily
Torso-like functions independently of Torso to regulate Drosophila
Activation of the Drosophila receptor tyrosine kinase Torso (Tor) only at the termini of the embryo is achieved by the localized expression of the maternal gene Torso-like (Tsl). Tor has a second function in the prothoracic gland as the receptor for prothoracicotropic hormone (PTTH) that initiates metamorphosis. Consistent with the function of Tor in this tissue, Tsl also localizes to the prothoracic gland and influences developmental timing. Despite these commonalities, in our studies of Tsl we unexpectedly found that tsl and tor have opposing effects on body size; tsl null mutants are smaller than normal, rather than larger as would be expected if the PTTH/Tor pathway was disrupted. We further found that whereas both genes regulate developmental timing, tsl does so independently of tor. Although tsl null mutants exhibit a similar length delay in time to pupariation to tor mutants, in tsl:tor double mutants this delay is strikingly enhanced. Thus, loss of tsl is additive rather than epistatic to loss of tor. We also find that phenotypes generated by ectopic PTTH expression are independent of tsl. Finally, we show that a modified form of tsl that can rescue developmental timing cannot rescue terminal patterning, indicating that Tsl can function via distinct mechanisms in different contexts. We conclude that Tsl is not just a specialized cue for Torso signaling but also acts independently of PTTH/Tor in the control of body size and the timing of developmental progression. These data highlight surprisingly diverse developmental functions for this sole Drosophila member of the perforin-like superfamily