Postnatal Smad3 Inactivation in Murine Smooth Muscle Cells Elicits a Temporally and Regionally Distinct Transcriptional Response.
Postnatal Smad3 Inactivation in Murine Smooth Muscle Cells Elicits a Temporally and Regionally Distinct Transcriptional Response.
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DOI：
10.3389/fcvm.2022.826495
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发表时间：
2022
影响因子：
3.6
通讯作者：
中科院分区：
文献类型：
--
作者：
转化生长因子-β（TGF-β）通路的正调节因子中的杂合、功能缺失突变导致遗传性胸主动脉瘤。目前尚不清楚初始信号传导缺陷是否以及如何在该途径的其余功能分支中触发次级信号传导上调，以及这是否有助于适应不良的血管重塑。为了在小鼠模型中检查这一过程，在该模型中可以评估对血管平滑肌细胞（VSMC）中出生后TGF-β信号传导的时间控制的部分干扰，我们使用VSMC特异性他莫昔芬诱导系统和条件等位基因，在围产期主动脉发育完成后，在6周龄时将Smad 3转染。这种干预引起主动脉根部扩张和组织学异常，升主动脉轻度受累。为了分析与疾病进展相关的早期和晚期事件，我们在缺失后10周和18周进行了比较性单细胞转录组学分析，此时主动脉扩张分别为不可检测和中度。在早期时间点，Smad 3失活导致细胞外基质成分和局灶性粘连的关键成分（包括整合素和锚定蛋白）的表达广泛减少，这在组织学上通过VSMC和弹性板层之间的连接丢失来反映。然而，在较晚的时间点，属于相同功能类别的几种转录物的表达正常化或甚至上调;这与编码TGF-β配体的转录物的上调和途径的负调节物的持续下调相关。要询问如何VSMC异质性可能会影响这种转变，我们研究了转录的变化，在每四个VSMC亚群确定，无论基因型，部分反映了近端到远端的解剖位置的基础上原位RNA杂交。对Smad 3缺乏的反应根据亚群而变化，并且VSMC亚群在主动脉根中过度表达，主动脉根是最容易扩张的部位，最显著地上调TGF-β配体和促致病因子，如血小板反应蛋白-1、血管紧张素转化酶和促炎介质。这些数据表明，Smad 3是维持局灶性粘连所必需的，并且与细胞外基质接触的丧失对每个VSMC亚群具有特异性后果，可能有助于主动脉中对扩张的区域易感性。
Heterozygous, loss of function mutations in positive regulators of the Transforming Growth Factor-β (TGF-β) pathway cause hereditary forms of thoracic aortic aneurysm. It is unclear whether and how the initial signaling deficiency triggers secondary signaling upregulation in the remaining functional branches of the pathway, and if this contributes to maladaptive vascular remodeling. To examine this process in a mouse model in which time-controlled, partial interference with postnatal TGF-β signaling in vascular smooth muscle cells (VSMCs) could be assessed, we used a VSMC-specific tamoxifen-inducible system, and a conditional allele, to inactivate Smad3 at 6 weeks of age, after completion of perinatal aortic development. This intervention induced dilation and histological abnormalities in the aortic root, with minor involvement of the ascending aorta. To analyze early and late events associated with disease progression, we performed a comparative single cell transcriptomic analysis at 10- and 18-weeks post-deletion, when aortic dilation is undetectable and moderate, respectively. At the early time-point, Smad3-inactivation resulted in a broad reduction in the expression of extracellular matrix components and critical components of focal adhesions, including integrins and anchoring proteins, which was reflected histologically by loss of connections between VSMCs and elastic lamellae. At the later time point, however, expression of several transcripts belonging to the same functional categories was normalized or even upregulated; this occurred in association with upregulation of transcripts coding for TGF-β ligands, and persistent downregulation of negative regulators of the pathway. To interrogate how VSMC heterogeneity may influence this transition, we examined transcriptional changes in each of the four VSMC subclusters identified, regardless of genotype, as partly reflecting the proximal-to-distal anatomic location based on in situ RNA hybridization. The response to Smad3-deficiency varied depending on subset, and VSMC subsets over-represented in the aortic root, the site most vulnerable to dilation, most prominently upregulated TGF-β ligands and pro-pathogenic factors such as thrombospondin-1, angiotensin converting enzyme, and pro-inflammatory mediators. These data suggest that Smad3 is required for maintenance of focal adhesions, and that loss of contacts with the extracellular matrix has consequences specific to each VSMC subset, possibly contributing to the regional susceptibility to dilation in the aorta.
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影响因子：
5.4
作者：
Bell V;Mitchell WA;Sigurðsson S;Westenberg JJ;Gotal JD;Torjesen AA;Aspelund T;Launer LJ;de Roos A;Gudnason V;Harris TB;Mitchell GF
通讯作者：
Mitchell GF
影响因子：
2.1
作者：
Azhar M;Ware SM
通讯作者：
Ware SM
影响因子：
8.3
作者：
Amighi, Jasmin;Hoke, Matthias;Wagner, Oswald
通讯作者：
Wagner, Oswald
DOI：
10.1093/bioinformatics/btp101
发表时间：
2009-04-15
期刊：
Bioinformatics (Oxford, England)
影响因子：
--
作者：
Bindea G;Mlecnik B;Hackl H;Charoentong P;Tosolini M;Kirilovsky A;Fridman WH;Pagès F;Trajanoski Z;Galon J
通讯作者：
Galon J
功能丝A突变损失的患者的胸动脉瘤：临床表征，遗传学和建议。
DOI：
10.1002/ajmg.a.38580
发表时间：
2018-03
期刊：
American journal of medical genetics. Part A
影响因子：
--
作者：
Chen MH;Choudhury S;Hirata M;Khalsa S;Chang B;Walsh CA
通讯作者：
Walsh CA