The opposite and antagonistic effects of the closely related POU family transcription factors Brn-3a and Brn-3b on the activity of a target promoter are dependent on differences in the POU domain

1994 ◽  
Vol 14 (10) ◽  
pp. 6907-6914
Author(s):  
P J Morris ◽  
T Theil ◽  
C J Ring ◽  
K A Lillycrop ◽  
T Moroy ◽  
...  

The Brn-3a, Brn-3b, and Brn-3c POU family transcription factors are closely related to one another and are members of the group IV subfamily of POU factors. Here we show that despite this close relationship, the factors have different effects on the activity of a target promoter: Brn-3a and Brn-3c stimulate the promoter whereas Brn-3b represses it. Moreover, Brn-3b can antagonize the stimulatory effect of Brn-3a on promoter activity and can also inhibit promoter activation by the Oct-2.1 POU factor. The difference in the transactivation activities of Brn-3a and Brn-3b is dependent upon the C-terminal region containing the POU domain of the two proteins, since exchange of this domain between the two factors converts Brn-3a into a repressor and Brn-3b into an activator.

1994 ◽  
Vol 14 (10) ◽  
pp. 6907-6914 ◽  
Author(s):  
P J Morris ◽  
T Theil ◽  
C J Ring ◽  
K A Lillycrop ◽  
T Moroy ◽  
...  

The Brn-3a, Brn-3b, and Brn-3c POU family transcription factors are closely related to one another and are members of the group IV subfamily of POU factors. Here we show that despite this close relationship, the factors have different effects on the activity of a target promoter: Brn-3a and Brn-3c stimulate the promoter whereas Brn-3b represses it. Moreover, Brn-3b can antagonize the stimulatory effect of Brn-3a on promoter activity and can also inhibit promoter activation by the Oct-2.1 POU factor. The difference in the transactivation activities of Brn-3a and Brn-3b is dependent upon the C-terminal region containing the POU domain of the two proteins, since exchange of this domain between the two factors converts Brn-3a into a repressor and Brn-3b into an activator.


Author(s):  
Annie Lang ◽  
Nancy Schwartz ◽  
Sharon Mayell

The study reported here compared how younger and older adults processed the same set of media messages which were selected to vary on two factors, arousing content and valence. Results showed that older and younger adults had similar arousal responses but different patterns of attention and memory. Older adults paid more attention to all messages than did younger adults. However, this attention did not translate into greater memory. Older and younger adults had similar levels of memory for slow-paced messages, but younger adults outperformed older adults significantly as pacing increased, and the difference was larger for arousing compared with calm messages. The differences found are in line with predictions made based on the cognitive-aging literature.


1975 ◽  
Vol 34 (02) ◽  
pp. 426-444 ◽  
Author(s):  
J Kahan ◽  
I Nohén

SummaryIn 4 collaborative trials, involving a varying number of hospital laboratories in the Stockholm area, the coagulation activity of different test materials was estimated with the one-stage prothrombin tests routinely used in the laboratories, viz. Normotest, Simplastin-A and Thrombotest. The test materials included different batches of a lyophilized reference plasma, deep-frozen specimens of diluted and undiluted normal plasmas, and fresh and deep-frozen specimens from patients on long-term oral anticoagulant therapy.Although a close relationship was found between different methods, Simplastin-A gave consistently lower values than Normotest, the difference being proportional to the estimated activity. The discrepancy was of about the same magnitude on all the test materials, and was probably due to a divergence between the manufacturers’ procedures used to set “normal percentage activity”, as well as to a varying ratio of measured activity to plasma concentration. The extent of discrepancy may vary with the batch-to-batch variation of thromboplastin reagents.The close agreement between results obtained on different test materials suggests that the investigated reference plasma could be used to calibrate the examined thromboplastin reagents, and to compare the degree of hypocoagulability estimated by the examined PIVKA-insensitive thromboplastin reagents.The assigned coagulation activity of different batches of the reference plasma agreed closely with experimentally obtained values. The stability of supplied batches was satisfactory as judged from the reproducibility of repeated measurements. The variability of test procedures was approximately the same on different test materials.


Author(s):  
Iwona Kowalczuk ◽  
Jerzy Gębski

The aim of the study was to examine whether, and to what extent, fear of contracting Covid-19 and compliance with the mandatory rules of isolation affected Polish adults’ nutritional behaviors. The online study was carried out during the first wave of the pandemic on a sample of 926 adults. Through cluster analysis, three groups of respondents were isolated: 1. People who fear a Covid-19 infection and follow the isolation rules (FFR), 2. People moderately afraid of the disease and following the rules loosely (MFFR), 3. People who are not afraid of the infection and do not follow the rules of isolation. (NFFR). The clusters were profiled with consideration of different aspects of eating behaviors as well as socio-demographic and economic features. The results of the study show a close relationship between the level of fear of contracting Covid-19 and the degree to which isolation rules are followed. These two factors were found to have a significant impact on eating behaviors, such as food purchases, eating patterns, and levels of consumption. It was stated that the FFR group changed their eating behaviors the most in terms of food purchasing, eating habits (excluding diversity and quality of diet), and food product consumption. The greatest stability in the majority of the analyzed areas of nutritional behaviors was observed in the MFFR cluster. The NFFR group shown the greatest decrease both in regularity and quality of their meals. This group also exhibited a significant increase in the consumption of alcoholic beverages. The results of the study can be useful in the decision making process when introducing restrictions or managing information. They also point to the need for extensive nutritional education focused on explaining the relationship between nutrition and health during a pandemic.


The present paper describes an investigation of diffusion in the solid state. Previous experimental work has been confined to the case in which the free energy of a mixture is a minimum for the single-phase state, and diffusion decreases local differences of concentration. This may be called ‘diffusion downhill’. However, it is possible for the free energy to be a minimum for the two-phase state; diffusion may then increase differences of concentration; and so may be called ‘diffusion uphill’. Becker (1937) has proposed a simple theoretical treatment of these two types of diffusion in a binary alloy. The present paper describes an experimental test of this theory, using the unusual properties of the alloy Cu 4 FeNi 3 . This alloy is single phase above 800° C and two-phase at lower temperatures, both the phases being face-centred cubic; the essential difference between the two phases is their content of copper. On dissociating from one phase into two the alloy develops a series of intermediate structures showing striking X-ray patterns which are very sensitive to changes of structure. It was found possible to utilize these results for a quantitative study of diffusion ‘uphill’ and ‘downhill’ in the alloy. The experimental results, which can be expressed very simply, are in fair agreement with conclusions drawn from Becker’s theory. It was found that Fick’s equation, dc / dt = D d2c / dx2 , can, within the limits of error, be applied in all cases, with the modification that c denotes the difference of the measured copper concentration from its equilibrium value. The theory postulates that D is the product of two factors, of which one is D 0f the coefficient of diffusion that would be measured if the alloy were an ideal solid solution. The theory is able to calculate D/D 0 , if only in first approximation, and the experiments confirm this calculation. It was found that in most cases the speed of diffusion—‘uphill’ or ‘downhill’—has the order of magnitude of D 0 . * Now with British Electrical Research Association.


1990 ◽  
Vol 52 (1) ◽  
pp. 773-791 ◽  
Author(s):  
H A Ingraham ◽  
V R Albert ◽  
R Chen ◽  
E B Crenshaw ◽  
H P E Xi He ◽  
...  

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Michael Hamm ◽  
Pierre Sohier ◽  
Valérie Petit ◽  
Jérémy H. Raymond ◽  
Véronique Delmas ◽  
...  

AbstractWhile the major drivers of melanoma initiation, including activation of NRAS/BRAF and loss of PTEN or CDKN2A, have been identified, the role of key transcription factors that impose altered transcriptional states in response to deregulated signaling is not well understood. The POU domain transcription factor BRN2 is a key regulator of melanoma invasion, yet its role in melanoma initiation remains unknown. Here, in a BrafV600EPtenF/+ context, we show that BRN2 haplo-insufficiency promotes melanoma initiation and metastasis. However, metastatic colonization is less efficient in the absence of Brn2. Mechanistically, BRN2 directly induces PTEN expression and in consequence represses PI3K signaling. Moreover, MITF, a BRN2 target, represses PTEN transcription. Collectively, our results suggest that on a PTEN heterozygous background somatic deletion of one BRN2 allele and temporal regulation of the other allele elicits melanoma initiation and progression.


1989 ◽  
Vol 9 (8) ◽  
pp. 3517-3523
Author(s):  
D P McDonnell ◽  
J W Pike ◽  
D J Drutz ◽  
T R Butt ◽  
B W O'Malley

The human osteocalcin gene is regulated in mammalian osteoblasts by 1,25(OH)2D3-dependent and -independent mechanisms. The sequences responsible for this activity have been mapped to within the -1339 region of the gene. We show here that this enhancer region functions analogously in Saccharomyces cerevisiae cells engineered to produce active 1,25(OH)2D3 receptor. When fused to the proximal promoter elements of the yeast iso-1-cytochrome c gene, the enhancer demonstrated substantial promoter activity. This activity was elevated further by 1,25(OH)2D3 when the reporter constructs were assayed in cells containing the 1,25(OH)2D3 receptor. This system affords a model for 1,25(OH)2D3 action and represents a simple assay system that will enable definition of the important cis-acting regulatory sequences within the osteocalcin gene and identification of their cognate transcription factors.


Author(s):  
Gazel Ser

Generalized Procrustes Analysis (GPA) is a multivariate statistic method that is used at the evaluation of sensory analyses in the food industry. GPA provides benefit in terms of decreasing the difference between the panellists and bringing the data obtained from different panellists together. In this study, the aim was to determine the effect of a pre-slaughter fasting period on sensory characteristics of lambs fed with different rations using GPA. Semi-trained panellists formed from twenty-six persons were requested for evaluation of the meat samples such as tenderness, juiciness, flavour and overall liking rated on a scale of 1(extremely dislike) to 9 (extremely good). The first two factors obtained by GPA explained 66.74% of total variability. As a result of the analysis, it was determined that 12 h and 24 h fasting of lambs fed barley supplemented with alfalfa hay were less preferable when compared to lambs fed alfalfa hay only. In addition, lambs in both groups with 48 h fasting were preferred less by the panellists. In conclusion, GPA analysis provides useful data concerning the sensitivity of each panellist in a sensory panel test.


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