14-3-3 acts as an intramolecular bridge to regulate cdc25B localization and activity

One of the major regulators of mitosis in somatic cells is cdc25B. cdc25B is tightly regulated at multiple levels. The final activation step involves the regulated binding of 14-3-3 proteins. Previous studies have demonstrated that Ser-323 is a primary 14-3-3 binding site in cdc25B, which influences its activity and cellular localization. 14-3-3 binding to this site appeared to interact with the N-terminal domain of cdc25B to regulate its activity. The presence of consensus 14-3-3 binding sites in the N-terminal domain suggested that the interaction is through direct binding of the 14-3-3 dimer to sites in the N-terminal domain. We have identified Ser-151 and Ser-230 in the N-terminal domain as functional 14-3-3 binding sites utilized by cdc25B in vivo. These low affinity sites cooperate to bind the 14-3-3 dimer bound to the high affinity Ser-323 site, thus forming an intramolecular bridge that constrains cdc25B structure to prevent access of the catalytic site. Loss of 14-3-3 binding to either N-terminal site relaxes cdc25B structure sufficiently to permit access to the catalytic site, and the nuclear export sequence located in the N-terminal domain. Mutation of the Ser-323 site was functionally equivalent to the mutation of all three sites, resulting in the complete loss of 14-3-3 binding, increased access of the catalytic site, and access to nuclear localization sequence.

Anaphoric choices in Japanese fictional novels: the discourse arrangement of noun phrases, zero and third person pronouns

By examining Japanese fictional novels, this article will discuss how anaphoric devices (noun phrases (NPs), third person pronouns (TPPs), and zero anaphors) are selected and arranged in a given discourse. The traditional view of anaphora considers the co-referential relationship between anaphoric devices to be syntagmatic; that is, a pronoun, for example, refers back to its antecedent. It also declares the hierarchical order of information values between anaphoric devices; NPs are semantically the most informative, indicating an episode boundary, and pronouns less informative. Furthermore, zero anaphora is the most referentially transparent, showing the most accessibility of a topic. However, real text shows the contrary. NPs occur frequently while there is no apparent discourse boundary, and the same episode is continuous. This is because zero anaphors and TPPs (if they occur) break down readily due to the nature of a forthcoming sentence and the NP is reinstated, in order to continue the same topic in a given discourse. Therefore, the article opposes the traditional view of anaphora. Based on the concept of text processing, using ‘mental representations’, this article will determine certain occurrence patterns of the three anaphoric devices.

OxyR acts as a repressor of catalase expression in Neisseria gonorrhoeae

It has been reported that Neisseria gonorrhoeae possesses a very high level of catalase activity, but the regulation of catalase expression has not been investigated extensively. In Escherichia coli and Salmonella enterica serovar Typhimurium, it has been demonstrated that OxyR is a positive regulator of hydrogen peroxide-inducible genes, including the gene encoding catalase. The oxyR gene from N. gonorrhoeae was cloned and used to complement an E. coli oxyR mutant, confirming its identity and function. The gene was inactivated by inserting a kanamycin resistance cassette and used to make a knockout allele on the chromosome of N. gonorrhoeae strain 1291. In contrast to E. coli, the N. gonorrhoeae oxyR::kan mutant expressed ninefold-more catalase activity and was more resistant to hydrogen peroxide killing than the wild type. These data are consistent with OxyR in N. gonorrhoeae acting as a repressor of catalase expression.

'Suitable mothers': lesbian and single women and the 'unborn' in Australian parliamentary discourse

Throughout the latter months of 2000 and early 2001, the Australian public, media and parliament were engaged in a long and emotive debate about motherhood. This debate constructed the two main protagonists, the unborn 'child' and the potential mother, with a variety of different and often oppositional identities. The article looks at the way that these subject identities interacted during the debate, starting from the premise that policy making has unintended and unacknowledged material outcomes, and using governmentality as a tool through which to analyse and understand processes of identity manipulation and resistance within policy making. The recent debate concerning the right of lesbian and single women to access new reproductive technologies in Australia is used as a case study. Nominally the debate was about access to IVF technology; in reality, however, the debate was about the governing of women and, in particular, the governing of motherhood identities. The article focuses on the parliamentary debate over the drafting of legislation designed to stop lesbian and single women from accessing these technologies, particularly the utilization of the 'unborn' subject within these debates as a device to discipline the identity of 'mother'.