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1.
Proc Biol Sci ; 281(1796): 20141700, 2014 Dec 07.
Article in English | MEDLINE | ID: mdl-25320163

ABSTRACT

The challenges of maintaining cohesion while making collective decisions in social or aggregating insects can result in the emergence of a leader or leaders. Larval aggregations of the steel-blue sawfly Perga affinis forage nocturnally, and some larvae lead the aggregation on foraging trips more often than expected by chance. We investigated the relationship between these leader and follower roles by comparing the weight and growth of individual larvae with different roles. Our observations reveal no significant difference between the growth of leaders and followers, suggesting that the role of leadership may not provide direct foraging benefits. However, by experimentally manipulating the social structure of larval aggregations, we found that individuals within aggregations that comprise a mixture of leaders and followers enjoy higher growth rates than those in aggregations comprising a single behavioural type. These data demonstrate, for the first time, individual benefits to maintaining a balance of leader and follower roles within larval aggregations, and highlight the importance of considering the perspectives of both leaders and followers when investigating the evolutionary significance of this behavioural variation within animal groups.


Subject(s)
Behavior, Animal , Hymenoptera/physiology , Social Behavior , Animal Distribution , Animals , Hymenoptera/growth & development , Larva/growth & development , Larva/physiology
2.
J Genet Couns ; 22(2): 175-87, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23007378

ABSTRACT

A model for practising genetic counselors to obtain clinical supervision via reciprocal peer observation and feedback was developed and trialled. The model was developed in response to a perceived lack of opportunity for immediate observational feedback for practising genetic counselors. The aims reached by consensus were to facilitate learning new approaches and skills, to revitalise current ways of practising, and to enhance supervision skills in a two-way process, where the observer learnt from the counselor, and vice-versa. The genetic counselors agreed on a process of paired reciprocal observation whereby the observer was present in the room during the counseling session, and a reflective feedback discussion was arranged within 24 h of the session. Four main themes emerged from analysis of the recorded discussions were (i) "I wasn't sure if I-": voicing of doubts or internal questions that occurred during session for the counselor conducting the session, (ii) "I really liked that": positive feedback and validation from the observer, (iii) "I wonder whether-": offering of alternative views, insights and strategies by the observer, and (iv) "That's a real thing for me to take away and think about": evidence of learning by both observers and counselors.


Subject(s)
Genetic Counseling , Models, Theoretical , Peer Review, Health Care , Humans , Victoria , Workforce
3.
Oncogene ; 14(24): 2899-916, 1997 Jun 19.
Article in English | MEDLINE | ID: mdl-9205097

ABSTRACT

Expression of the Epstein-Barr virus (EBV) transforming LMP1 in B cells activates the transcription factor NF-kappaB and induces phenotypic changes through two distinct domains in the cytoplasmic C-terminus of the protein. The aa 187-231 domain of LMP1, which is important for growth transformation, binds tumour necrosis factor (TNF) receptor associated factor (TRAF) 1 and TRAF3 and this interaction mediates subsequent signalling events. The TRAFs also associate with CD40, a member of the TNFR family, which upon ligation activates NF-kappaB and induces phenotypic changes similar to those mediated by LMP1. This study demonstrates that LMP1 expression in carcinoma cell lines and SV40-transformed keratinocytes results in induction of the pleiotropic cytokine interleukin 6 (IL6), an effect which is also observed upon CD40 ligation. The mechanism by which either LMP1 expression or CD40 ligation induces IL6 production was found to be NF-kappaB-dependent. Mutational analysis identified domains in the C-terminus of LMP1 which are important for NF-kappaB activation and IL6 secretion. LMP1 and CD40 share a common PxQxT core TRAF binding motif and mutations in or adjacent to this sequence impaired the ability of LMP1 or CD40 to induce NF-kappaB activation and IL6 secretion. The importance of TRAF interactions in mediating these effects was confirmed using dominant negative TRAF2 and TRAF3 mutants which also identified differences in the signalling events mediated by the two NF-kappaB activating domains of LMP1. A20, an anti-apoptotic protein which interacts with TRAF2 and blocks CD40-mediated NF-kappaB activity, also blocked NF-kappaB and IL6 secretion in LMP1-transfected epithelial cells. These results suggest that LMP1 regulates IL6 production in epithelial cells in a manner similar to CD40 ligation and implicate TRAFs as common mediators in the transduction of signals generated via the CD40 and LMP1 pathways. As a role for IL6 in regulating epithelial cell growth has previously been suggested, the control of IL6 secretion via the CD40 and LMP1 pathways may have implications for the growth of both normal and transformed epithelial cells.


Subject(s)
CD40 Antigens/physiology , Herpesvirus 4, Human/genetics , Interleukin-6/biosynthesis , NF-kappa B/physiology , Proteins/physiology , Receptors, Tumor Necrosis Factor/physiology , Viral Matrix Proteins/physiology , Amino Acid Sequence , Binding Sites , CD40 Antigens/genetics , Cell Division/physiology , Cell Transformation, Viral/physiology , Epithelium/embryology , Epithelium/physiology , Female , HeLa Cells/metabolism , HeLa Cells/physiology , Herpesvirus 4, Human/physiology , Humans , Interleukin-6/metabolism , Molecular Sequence Data , Ovarian Neoplasms/genetics , Ovarian Neoplasms/metabolism , Protein Structure, Tertiary , Proteins/metabolism , Receptors, Tumor Necrosis Factor/metabolism , TNF Receptor-Associated Factor 1 , TNF Receptor-Associated Factor 2 , TNF Receptor-Associated Factor 3 , Transfection , Tumor Cells, Cultured , Urinary Bladder Neoplasms/genetics , Urinary Bladder Neoplasms/metabolism , Viral Matrix Proteins/genetics
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