Perturbation of Cytokinin and Ethylene-signalling Pathways Explain the Strong Rooting Phenotype Exhibited by Arabidopsis Expressing the Schizosaccharomyces Pombe mitotic inducer, cdc25.

Background Entry into mitosis is regulated by cyclin dependent kinases that in turn are phosphoregulated. In most eukaryotes, phosphoregulation is through WEE1 kinase and CDC25 phosphatase. In higher plants a homologous CDC25 gene is unconfirmed and hence the mitotic inducer Schizosaccharomyces pombe (Sp) cdc25 has been used as a tool in transgenic plants to probe cell cycle function. Expression of Spcdc25 in tobacco BY-2 cells accelerates entry into mitosis and depletes cytokinins; in whole plants it stimulates lateral root production. Here we show, for the first time, that alterations to cytokinin and ethylene signaling explain the rooting phenotype elicited by Spcdc25 expression in Arabidopsis. Results Expressing Spcdc25 in Arabidopsis results in increased formation of lateral and adventitious roots, a reduction of primary root width and more isodiametric cells in the root apical meristem (RAM) compared with wild type. Furthermore it stimulates root morphogenesis from hypocotyls when cultured on two way grids of increasing auxin and cytokinin concentrations. Microarray analysis of seedling roots expressing Spcdc25 reveals that expression of 167 genes is changed by > 2-fold. As well as genes related to stress responses and defence, these include 19 genes related to transcriptional regulation and signaling. Amongst these was the up-regulation of genes associated with ethylene synthesis and signaling. Seedlings expressing Spcdc25 produced 2-fold more ethylene than WT and exhibited a significant reduction in hypocotyl length both in darkness or when exposed to 10 ppm ethylene. Furthermore in Spcdc25 expressing plants, the cytokinin receptor AHK3 was down-regulated, and endogenous levels of iPA were reduced whereas endogeous IAA concentrations in the roots increased. Conclusions We suggest that the reduction in root width and change to a more isodiametric cell phenotype in the RAM in Spcdc25 expressing plants is a response to ethylene over-production. The increased rooting phenotype in Spcdc25 expressing plants is due to an increase in the ratio of endogenous auxin to cytokinin that is known to stimulate an increased rate of lateral root production. Overall, our data reveal important cross talk between cell division and plant growth regulators leading to developmental changes.

Social Capital in Jordan: Wasta in Employment Selection

Social capital has emerged as a concept of great interest and potential to help understand and explain how social structures and networks impact political, social and business practices at the collective and individual levels. The basic premise is: investment in social relations will yield expected returns. Extant research has largely focused on the West; our knowledge of how social capital plays out in the Middle East is limited. We marry social capital with ‘wasta’, the strong family and tribal based connections secured in networks in the Arab world, and investigate HR managers’ perceptions of wasta in employment selection in Jordan. Often use of wasta in employment selection is related to favouritism and nepotism and the many negative outcomes of not adhering to merit-based selection. Through in-depth interview data we reveal a more nuanced and multifaceted view of wasta in employment selection. When examined through the social capital lens six distinct themes emerge: (i) wasta as an enabler to get jobs, (ii) wasta as social ties/ solidarity, (iii) wasta as a method to transfer/ attain information, (iv) wasta as a guide in decision-making, (v) wasta as an exchange, and (vi) wasta as pressure. Our findings confirm that at times wasta grants individuals unfair access to employment that is beyond their qualifications, skills, knowledge and/ or abilities. However, organisational context is relevant. In banking, not all roles are open to wasta. Where the possible negative impact on the organisation poses too great a risk HR managers feel able to resist even strong wasta. Context also emerges as being of key importance with regards to the background and business model of an organisation. Family businesses tend to operate wasta more frequently and extensively using tribal connections, religious networks and geographical area based networks as a key source in hiring. Despite globalisation and international nature of banking, wasta and tribalism feature strongly in daily business conduct in Jordan. Our paper illuminates the positive effects of wasta, e.g.as a method to transfer information, together with discussion on the dangers of ‘cloning’, a (lack of diversity), and the dangers of an incompetent workforce .