Cryptorchidism and Infertility in Rats with Targeted Disruption of the Adamts16 Locus

A Disintegrin And Metalloproteinase with ThromboSpondin motifs16 (ADAMTS-16) is a member of a family of metalloproteinases. Using a novel zinc-finger nuclease based gene-edited rat model harboring a targeted mutation of the Adamts16 locus, we previously reported this gene to be linked to blood pressure regulation. Here we document our observation with this model that Adamts16 is essential for normal development of the testis. Absence of Adamts16 in the homozygous Adamts16(mutant) males resulted in cryptorchidism and male sterility. Heterozygous Adamts16(mutant) males were normal, indicating that this is a recessive trait. Testes of homozygous Adamts16(mutant) males were significantly smaller with significant histological changes associated with the lack of sperm production. Temporal histological assessments of the testis demonstrated that the seminiferous tubules did not support active spermatogenesis, but progressively lost germ cells, accumulated vacuoles and did not have any sperm. These observations, taken together with our previous report of renal abnormalities observed with the same Adamts16(mutant) rats, suggest an important mechanistic link between Adamts16 and the functioning of the male genitourinary system

Ciliary Polycystin-2 Is a Mechanosensitive Calcium Channel Involved in Nitric Oxide Signaling Cascades

Cardiovascular complications such as hypertension are a continuous concern in patients with autosomal dominant polycystic kidney disease (ADPKD). The PKD2 encoding for polycystin-2 is mutated in ≈15% of ADPKD patients. Here, we show that polycystin-2 is localized to the cilia of mouse and human vascular endothelial cells. We demonstrate that the normal expression level and localization of polycystin-2 to cilia is required for the endothelial cilia to sense fluid shear stress through a complex biochemical cascade, involving calcium, calmodulin, Akt/PKB, and protein kinase C. In response to fluid shear stress, mouse endothelial cells with knockdown or knockout of Pkd2 lose the ability to generate nitric oxide (NO). Consistent with mouse data, endothelial cells generated from ADPKD patients do not show polycystin-2 in the cilia and are unable to sense fluid flow. In the isolated artery, we further show that ciliary polycystin-2 responds specifically to shear stress and not to mechanical stretch, a pressurized biomechanical force that involves purinergic receptor activation. We propose a new role for polycystin-2 in transmitting extracellular shear stress to intracellular NO biosynthesis. Thus, aberrant expression or localization of polycystin-2 to cilia could promote high blood pressure because of inability to synthesize NO in response to an increase in shear stress (blood flow)

Age differences in gain- and loss-motivated attention

Adaptive gain theory (Aston-Jones & Cohen, 2005) suggests that the phasic release of norepinephrine (NE) to cortical areas reflects changes in the utility of ongoing tasks. In the context of aging, this theory raises interesting questions, given that the motivations of older adults differ from those of younger adults. According to socioemotional selectivity theory (Carstensen, Isaacowitz, & Charles, 1999), aging is associated with greater emphasis on emotion-regulation goals, leading older adults to prioritize positive over negative information. This suggests that the phasic release of NE in response to threatening stimuli may be diminished in older adults. In the present study, younger adults (aged 18–34 years) and older adults (60–82 years) completed the Attention Network Test (ANT), modified to include an incentive manipulation. A behavioral index of attentional alerting served as a marker of phasic arousal. For younger adults, this marker correlated with the effect of both gain and loss incentives on performance. For older adults, in contrast, the correlation between phasic arousal and incentive sensitivity held for gain incentives only. These findings suggest that the enlistment of phasic NE activity may be specific to approach-oriented motivation in older adults

QTL mapping of rat blood pressure loci on RNO1 within a homologous region linked to human hypertension on HSA15.

Fine-mapping of regions linked to the inheritance of hypertension is accomplished by genetic dissection of blood pressure quantitative trait loci (BP QTLs) in rats. The goal of the current study was to further fine-map two genomic regions on rat chromosome 1 with opposing blood pressure effects (BP QTL1b1 and BP QTL1b1a), the homologous region of which on human chromosome 15 harbors BP QTLs. Two new substrains were constructed and studied from the previously reported BP QTL1b1, one having significantly lower systolic BP by 17 mmHg than that of the salt-sensitive (S) rat (P = 0.007). The new limits of BP QTL1b1 were between 134.09 Mb and 135.40 Mb with a 43% improvement from the previous 2.31 Mb to the current 1.31 Mb interval containing 4 protein-coding genes (Rgma, Chd2, Fam174b, and St8sia2), 2 predicted miRNAs, and 4 lncRNAs. One new substrain was constructed and studied from the previously reported BPQTL1b1a having a significantly higher systolic BP by 22 mmHg (P = 0.006) than that of the S rat. The new limits of BPQTL1b1a were between 133.53 Mb and 134.52 Mb with a 32% improvement from the previous1.45 Mb to the current 990.21 Kb interval containing 1 protein-coding gene, Mctp2, and a lncRNA. The congenic segments of these two BP QTLs overlapped between 134.09 Mb and 134.52 Mb. No exonic variants were detected in any of the genes. These findings reiterate complexity of genetic regulation of BP within QTL regions, where elements beyond protein-coding sequences could be factors in controlling BP

Deep transcriptomic profiling of Dahl salt-sensitive rat kidneys with mutant form of Resp18.

Expression of Regulated endocrine specific protein 18 (Resp18) is localized in numerous tissues and cell types; however, its exact cellular function is unknown. We previously showed that targeted disruption of the Resp18 locus in the Dahl SS (SS) rat (Resp18(mutant)) results in higher blood pressure (BP), increased renal fibrosis, increased urinary protein excretion, and decreased mean survival time following a chronic (6 weeks) 2% high salt (HS) diet compared with the SS rat. Based on this prominent renal injury phenotype, we hypothesized that targeted disruption of Resp18 in the SS rat promotes an early onset hypertensive-signaling event through altered signatures of the renal transcriptome in response to HS. To test this hypothesis, both SS and Resp18(mutant) rats were exposed to a 7-day 2% HS diet and BP was recorded by radiotelemetry. After a 7-day exposure to the HS diet, systolic BP was significantly increased in the Resp18(mutant) rat compared with the SS rat throughout the circadian cycle. Therefore, we sought to investigate the renal transcriptomic response to HS in the Resp18(mutant) rat. Using RNA sequencing, Resp18(mutant) rats showed a differential expression of 25 renal genes, including upregulation of Ren. Upregulation of renal Ren and other differentially expressed genes were confirmed via qRT-PCR. Moreover, circulating renin activity was significantly higher in the Resp18(mutant) rat compared with the WT SS rat after 7 days on HS. Collectively, these observations demonstrate that disruption of the Resp18 gene in the SS rat is associated with an altered renal transcriptomics signature as an early response to salt load

When is a park more than a park?:Rethinking the role of parks as 'shared space' in post-conflict Belfast.

© 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).With the signing of the Belfast Agreement, Belfast (Northern Ireland, UK) entered a new phase of urban development. Moving away from notions of division, Belfast City Council envisaged an inclusive and accessible city. Over a 20-year period, there have been significant changes in Belfast’s physical, socio-cultural, and political structure, reframing the city as a post-conflict space. However, there has been limited analysis of the role of parks in this process. This paper examines perceptions of parks, asking whether the promotion of a “shared spaces” policy aligns with local use. Through a mixed-methods approach, park users were surveyed to reflect on the meanings of parks in the city. We argue that although residual interpretations associated with historical socio-cultural divisions remain, parks are predominately multi-community amenities. The analysis illustrates that although destination parks attract greater patronage, there is visible clustering around ‘anchor’ sites at the local scale, especially in neighbourhoods with significant Catholic or Protestant identities.Peer reviewe

When Is a Park More Than a Park? Rethinking the Role of Parks as "Shared Space" in Post-Conflict Belfast

With the signing of the Belfast Agreement, Belfast (Northern Ireland, UK) entered a new phase of urban development. Moving away from notions of division, Belfast City Council envisaged an inclusive and accessible city. Over a 20-year period, there have been significant changes in Belfast’s physical, socio-cultural, and political structure, reframing the city as a post-conflict space. However, there has been limited analysis of the role of parks in this process. This paper examines perceptions of parks, asking whether the promotion of a “shared spaces” policy aligns with local use. Through a mixed-methods approach, park users were surveyed to reflect on the meanings of parks in the city. We argue that although residual interpretations associated with historical socio-cultural divisions remain, parks are predominately multi-community amenities. The analysis illustrates that although destination parks attract greater patronage, there is visible clustering around ‘anchor’ sites at the local scale, especially in neighbourhoods with significant Catholic or Protestant identities.</jats:p

Detection of <i>Adamts16</i> mRNA within the rat testes.

<p>Presence of <i>Adamts16</i> mRNA in the testes of age-matched 30 day old animals was determined by <i>in-situ</i> hybridization as described under the methods section. <i>β-actin</i> was used as a control.</p