Analysis of the asymmetrically expressed Ablim1 locus reveals existence of a lateral plate Nodal-independent left sided signal and an early, left-right independent role for nodal flow
BMC DEVELOPMENTAL BIOLOGY
Authors: Stevens, Jonathan; Ermakov, Alexander; Braganca, Jose; Hilton, Helen; Underhill, Peter; Bhattacharya, Shoumo; Brown, Nigel A.; Norris, Dominic P.
Abstract
Background: Vertebrates show clear asymmetry in left-right (L-R) patterning of their organs and associated vasculature. During mammalian development a cilia driven leftwards flow of liquid leads to the left-sided expression of Nodal, which in turn activates asymmetric expression of the transcription factor Pitx2. While Pitx2 asymmetry drives many aspects of asymmetric morphogenesis, it is clear from published data that additional asymmetrically expressed loci must exist. Results: A L-R expression screen identified the cytoskeletally-associated gene, actin binding lim protein 1 (Ablim1), as asymmetrically expressed in both the node and left lateral plate mesoderm (LPM). LPM expression closely mirrors that of Nodal. Significantly, Ablim1 LPM asymmetry was detected in the absence of detectable Nodal. In the node, Ablim1 was initially expressed symmetrically across the entire structure, resolving to give a peri-nodal ring at the headfold stage in a flow and Pkd2-dependent manner. The peri-nodal ring of Ablim1 expression became asymmetric by the mid-headfold stage, showing stronger right than left-sided expression. Node asymmetry became more apparent as development proceeded; expression retreated in an anticlockwise direction, disappearing first from the left anterior node. Indeed, at early somite stages Ablim1 shows a unique asymmetric expression pattern, in the left lateral plate and to the right side of the node. Conclusion: Left LPM Ablim1 is expressed in the absence of detectable LPM Nodal, clearly revealing existence of a Pitx2 and Nodal-independent left-sided signal in mammals. At the node, a previously unrecognised action of early nodal flow and Pkd2 activity, within the pit of the node, influences gene expression in a symmetric manner. Subsequent Ablim1 expression in the peri-nodal ring reveals a very early indication of L-R asymmetry. Ablim1 expression analysis at the node acts as an indicator of nodal flow. Together these results make Ablim1 a candidate for controlling aspects of L-R identity and patterning.
LncRNA ZNF667-AS1 Promotes ABLIM1 Expression by Adsorbing microRNA-1290 to Suppress Nasopharyngeal Carcinoma Cell Progression
ONCOTARGETS AND THERAPY
Authors: Chen, Xi; Huang, Yaping; Shi, Dianyu; Nie, Chuan; Luo, Yiping; Guo, Liangfen; Zou, Yu; Xie, Chun
Abstract
Background: Recently, long non-coding RNAs (lncRNAs) have been elucidated to play essential roles in cancers, and the recognition of lncRNA expression patterns in nasopharyngeal carcinoma (NPC) may be helpful for indicating novel mechanisms underlying NPC carcinogenesis. Herein, we conducted this study to probe into the function of lncRNA ZNF667-AS1 in NPC progression with the involvement of microRNA-1290 (miR-1290) and actin-binding LIM protein 1 (ABLIM1). Materials and Methods: In silico analysis screened differentially expressed genes and miRNAs in NPC and predicted potential mechanisms. ZNF667-AS1 expression was detected in NPC tissues and cells. The gain-and-loss function assays were performed to explore the effects of lncRNA ZNF667-AS1 and miR-1290 in NPC cell biological behaviors. In vivo experiments were further conducted to confirm the in vitro results. Results: In silico analysis predicted that ZNF667-AS1 was diminished in NPC, which may downregulate ABLIM1 through sponging miR-1290. ZNF667-AS1 was poorly expressed in NPC tissues and cells, and overexpression of ZNF667-AS1 inhibited growth of NPC cells. ZNF667-AS1 competitively bound with miR-1290, thereby upregulating ABLIM1. miR-1290 resulted in the promotion of NPC cell progression by suppressing ABLIM1. Overexpression of ZNF667-AS1 or suppression of miR-1290 inhibited tumorigenicity of NPC cells in vivo. Conclusion: This study highlights that lncRNA ZNF667-AS1 promotes ABLIM1 expression by sponging miR-1290 to suppress NPC cell progression.