A distal region of the human TGM1 promoter is required for expression in transgenic mice and cultured keratinocytes

BACKGROUND: TGM1(transglutaminase 1) is an enzyme that crosslinks the cornified envelope of mature keratinocytes. Appropriate expression of the TGM1 gene is crucial for proper keratinocyte function as inactivating mutations lead to the debilitating skin disease, lamellar ichthyosis. TGM1 is also expressed in squamous metaplasia, a consequence in some epithelia of vitamin A deficiency or toxic insult that can lead to neoplasia. An understanding of the regulation of this gene in normal and abnormal differentiation states may contribute to better disease diagnosis and treatment. METHODS: In vivo requirements for expression of the TGM1 gene were studied by fusing various lengths of promoter DNA to a reporter and injecting the DNA into mouse embryos to generate transgenic animals. Expression of the reporter was ascertained by Western blotting and immunohistochemistry. Further delineation of a transcriptionally important distal region was determined by transfections of progressively shortened or mutated promoter DNA into cultured keratinocytes. RESULTS: In vivo analysis of a reporter transgene driven by the TGM1 promoter revealed that 1.6 kilobases, but not 1.1 kilobases, of DNA was sufficient to confer tissue-specific and cell layer-specific expression. This same region was responsible for reporter expression in tissues undergoing squamous metaplasia as a response to vitamin A deprivation. Mutation of a distal promoter AP1 site or proximal promoter CRE site, both identified as important transcriptional elements in transfection assays, did not prevent appropriate expression. Further searching for transcriptional elements using electrophoretic mobility shift (EMSA) and transfection assays in cultured keratinocytes identified two Sp1 elements in a transcriptionally active region between -1.6 and -1.4 kilobases. While mutation of either Sp1 site or the AP1 site singly had only a small effect, mutation of all three sites eliminated nearly all the transcriptional activity. CONCLUSIONS: A distal region of the TGM1 gene promoter, containing AP1 and Sp1 binding sites, is evolutionarily conserved and responsible for high level expression in transgenic mice and in transfected keratinocyte cultures

Expression of estrogen receptors in the hypothalamo-pituitary-ovarian axis in middle-aged rats after re-instatement of estrus cyclicity

During reproductive aging female rats enter an anovulatory state of persistent estrus (PE). In an animal model of re-instatement of estrus cyclicity in middle-aged PE rats we injected the animals with progesterone (0.5 mg progesterone/kg body weight) at 12:00 for 4 days whereas control animals received corn oil injections. After the last injection animals were analyzed at 13:00 and 17:00. Young regular cycling rats served as positive controls and were assessed at 13:00 and 17:00 on proestrus. Progesterone treatment of middle-aged PE rats led to occurrence of luteinizing hormone (LH), follicle stimulating hormone (FSH), and prolactin surges in a subset of animals that were denoted as responders. Responding middle-aged rats displayed a reduction of ER-β mRNA in the preoptic area which was similar to the effect in young rats. Within the mediobasal hypothalamus, only young rats showed a decline of ER-α mRNA expression. A decrease of ER-α mRNA levels in the pituitary was observed in progesterone-responsive rats and in young animals. ER-β mRNA expression was reduced in young regular cycling rats. ER-β mRNA levels in the ovary were reduced following progesterone treatment in PE rats and in young rats. Taken together our data show that cyclic administration of progesterone reinstates ovulatory cycles in intact aging females which have already lost their ability to display spontaneous cyclicity. This treatment leads to the occurrence of preovulatory LH, FSH and prolactin surges which are accompanied by differential modulation of ERs in the hypothalamus, the pituitary and the ovary

FittsFarm: Comparing Children’s Drag-and-Drop Performance Using Finger and Stylus Input on Tablets

We used a two-dimensional Fitts’ law task to compare finger and stylus input with children when performing drag-and-drop tasks on a tablet. Twenty-eight children completed the study. Drag-and-drop performance was significantly better using a low-cost stylus compared to finger input. Throughput was 9% higher for stylus input (2.55bps) compared to finger input (2.34bps). Error rates were 35% percent higher for finger input (12.6%) compared to stylus input (9.3%). Error rates approximately doubled with smaller targets. There was no significant difference observed for movement time between input methods. Findings indicate schools should consider providing children with a low-cost stylus for educational activities on tablets

Learning literacy: Engaging with print and digital texts in the first year of school

This chapter investigates the possibilities available when teachers and children engage in learning and teaching literacies with print and digital materials. The data reported was collected as part of a 5-year school reform project set in one school in a high-poverty community. The main project aimed to investigate whether a focus on teacher professionalism, collaborative curriculum planning and reshaping pedagogy could have a positive effect on student outcomes. The student population at the school was diverse, and there was an identified need to connect substantively with the outside school lives of the student cohort more effectively. Here we report on the results of one component of the larger project where the teacher of one preparatory class and researchers worked collaboratively to digitise the curriculum. This shared work led to the introduction of new texts, tools and technologies into the curriculum. The analysis of work samples, interview transcripts and classroom observations followed the developing literacy capacities of the young students throughout the year. Drawing on socio-material understandings, we consider the tools, resources and technologies featured as these students learnt about and with literacy. We also provide a vignette of the literacy journey of one student as a focussed example of print and digital literacy learning achievement in the class. The findings provide insight into the positive impact of literacy teaching and learning that takes account of students’ engagement with digital and print texts within early years’ classrooms.</p