The UFM1 cascade times mitosis entry associated with microcephaly.
- 作者列表："Yu L","Li G","Deng J","Jiang X","Xue J","Zhu Y","Huang W","Tang B","Duan R
:Posttranslational modifications enhance the functional diversity of the proteome by modifying the substrates. The UFM1 cascade is a novel ubiquitin-like modification system. The mutations in UFM1, its E1 (UBA5) and E2 (UFC1), have been identified in patients with microcephaly. However, its pathological mechanisms remain unclear. Herein, we observed the disruption of the UFM1 cascade in Drosophila neuroblasts (NBs) decreased the number of NBs, leading to a smaller brain size. The lack of ufmylation in NBs resulted in an increased mitotic index and an extended G2/M phase, indicating a defect in mitotic progression. In addition, live imaging of the embryos revealed an impaired E3 ligase (Ufl1) function resulted in premature entry into mitosis and failed cellularization. Even worse, the embryonic lethality occurred as early as within the first few mitotic cycles following the depletion of Ufm1. Knockdown of ufmylation in the fixed embryos exhibited severe phenotypes, including detached centrosomes, defective microtubules, and DNA bridge. Furthermore, we observed that the UFM1 cascade could alter the level of phosphorylation on tyrosine-15 of CDK1 (pY15-CDK1), which is a negative regulator of the G2 to M transition. These findings yield unambiguous evidence suggesting that the UFM1 cascade is a microcephaly-causing factor that regulates the progression of the cell cycle at mitosis phase entry.
: 翻译后修饰通过修饰底物增强蛋白质组的功能多样性。UFM1 级联反应是一种新型的泛素样修饰系统。UFM1 的突变，其E1 (UBA5) 和E2 (UFC1)，已经在小头畸形患者中被发现。然而，其病理机制仍不清楚。在此，我们观察到果蝇神经母细胞 (NBs) 中UFM1 级联的破坏降低了NBs的数量，导致脑体积变小。NBs中缺乏ufmylation导致有丝分裂指数增加，G2/M期延长，表明有丝分裂进程存在缺陷。此外，胚胎的实时成像显示E3 连接酶 (Ufl1) 功能受损导致过早进入有丝分裂，细胞化失败。更糟糕的是，胚胎致死早在ufm1 耗尽后的最初几个有丝分裂周期内就发生了。固定胚胎中ufmylation的敲除表现出严重的表型，包括分离的中心体、缺陷的微管和DNA桥。此外，我们观察到UFM1 级联反应可以改变CDK1 (pY15-CDK1) 酪氨酸-15 上的磷酸化水平，这是G2 到M转换的负调控因子。这些发现产生了明确的证据，表明UFM1 级联反应是一种小头症引起的因子，调节有丝分裂阶段进入的细胞周期的进程。
METHODS::Impairments in social cognition have been frequently described in 22q11.2 deletion syndrome (22q11.2DS) and are thought to be a hallmark of difficulties in social interactions. The present study addresses aspects that are critical for everyday social cognitive functioning but have received little attention so far. Sixteen children with 22q11.2DS and 22 controls completed 1 task of facial expression recognition, 1 task of attribution of facial expressions to faceless characters involved in visually presented social interactions, and 1 task of attribution of facial expressions to characters involved in aurally presented dialogues. All three tasks have in common to involve processing of emotions. All participants also completed two tasks of attention and two tasks of visual spatial perception, and their parents completed some scales regarding behavioural problems of their children. Patients performed worse than controls in all three tasks of emotion processing, and even worse in the second and third tasks. However, they performed above chance level in all three tasks, and the results were independent of IQ, age and gender. The analysis of error patterns suggests that patients tend to coarsely categorize situations as either attractive or repulsive and also that they have difficulties in differentiating emotions that are associated with threats. An isolated association between the tasks of emotion and behaviour was found, showing that the more frequently patients with 22q11.2DS perceive happiness where there is not, the less they exhibit aggressive behaviour.
METHODS:BACKGROUND:We describe the first radiographic clinic in the literature for DDH and how this novel clinic can significantly improve the efficiency and cost-effectiveness of service in a tertiary referral centre. AIMS:A radiographic clinic for the management of developmental dysplasia of the hip was introduced in 2017 in our institution. We performed a detailed cost analysis to assess the economic savings made with the introduction of this new clinic. We assessed the efficiency of the service by identifying how many unnecessary outpatient visits were prevented. We also assessed the difference in times from referral to review between the two clinics. METHODS:Analysis of the clinic activity in 2017 was possible as all data was collected prospectively by the DDH CNS and stored in our database. Cost analysis was performed, and the savings made per patient along with the financial benefit to our institution was recorded. RESULTS:The new radiographic clinic reduced the cost of reviewing one patient by €162.51 per patient. There was a 73% discharge rate from the clinic which prevented 251 unnecessary patient visits to the outpatient department over the course of the year. There was a significant 11-day reduction in waiting times between referral and review when comparing the radiographic to the conventional clinic (p < 0.05). CONCLUSIONS:A radiographic clinic for the management of developmental dysplasia of the hip has a significant effect on the efficiency and overall cost-effectiveness of service provision in a tertiary referral centre.
METHODS:INTRODUCTION:Triple pelvic osteotomy (TPO) involves periacetabular osteotomies of the ilium, ischium, and pubis to reorient the acetabulum. This operation is indicated in certain situations for the treatment of developmental dysplasia of the hip, dysplastic neuromuscular hips, and for containment of the femoral head in cases of Legg-Calvé-Perthes disease. METHODS:This retrospective cohort study compares radiographic outcomes of patients who underwent TPO using two different techniques and describes a novel single-incision direct lateral approach. TPO was performed on 22 patients by the senior author. The first 10 patients underwent TPO through a single-incision anterolateral approach. The last 12 patients underwent TPO using the direct lateral approach. Preoperative and postoperative pelvic radiographs were reviewed for each patient, and the migration index and center-edge angle were recorded. RESULTS:The migration index and center-edge angle were evaluated and were not found to be significantly different between the anterolateral and direct lateral groups. The direct lateral approach is described. CONCLUSION:The direct lateral approach for TPO is equivalent to the anterolateral approach on radiographic evaluation. Advantages of the direct lateral approach include direct visualization of the ischial osteotomy, effective mobilization of the acetabulum, and safety of the sciatic nerve.