Study of MicroRNAs Related to the Liver Regeneration of the Whitespotted Bamboo Shark,Chiloscyllium plagiosum

Abstract

To understand the mechanisms of liver regeneration better to promote research examining liver diseases and marine biology, normal and regenerative liver tissues of Chiloscyllium plagiosum were harvested 0 h and 24 h after partial hepatectomy (PH) and used to isolate small RNAs for miRNA sequencing. In total, 91 known miRNAs and 166 putative candidate (PC) miRNAs were identified for the first time in Chiloscyllium plagiosum. Through target prediction and GO analysis, 46 of 91 known miRNAs were screened specially for cellular proliferation and growth. Differential expression levels of three miRNAs (xtr-miR-125b, fru-miR-204, and hsa-miR-142-3p_R-1) related to cellular proliferation and apoptosis were measured in normal and regenerating liver tissues at 0 h, 6 h, 12 h, and 24 h using real-time PCR. The expression of these miRNAs showed a rising trend in regenerative liver tissues at 6 h and 12 h but exhibited a downward trend compared to normal levels at 24 h. Differentially expressed genes were screened in normal and regenerating liver tissues at 24 h by DDRT-PCR, and ten sequences were identified. This study provided information regarding the function of genes related to liver regeneration, deepened the understanding of mechanisms of liver regeneration, and resulted in the addition of a significant number of novel miRNAs sequences to GenBank.

Detection of piRNAs in whitespotted bamboo shark liver

“…We confirmed that some microRNAs play a regulatory role in the process of liver regeneration and immunity response (Lu et al, 2013;Zhang et al, 2013). The increasing number of studies on microRNAs that are currently taking place revealed a new type of small RNA, namely piRNA, which has resulted in increasing attention to this research field.…”

“…After cutting along the abdominal skin and muscle layer, a one-third partial hepatectomy of the shark liver was performed on the right as normal liver tissue (LN), and the liver was washed with saline and rapidly frozen in liquid nitrogen . After liver resection, the wounds were sutured, and the shark was returned to the aquarium and continuously fed for approximately 3 h. We then collected the remaining part of the cut edge of the liver as the 3 h regenerative liver tissue (LR3) (Lu et al, 2013;Zhang et al, 2013). The LN and LR3 samples frozen in liquid nitrogen were sent to Lianchuan Biological Technology Co., Ltd., in Hangzhou for deep sequencing.…”

Wound-healing capabilities of whale sharks (Rhincodon typus) and implications for conservation management

“…Although a more in-depth analysis of tissue structure is required for a complete understanding of this case, it can be noted that this unique observation was visually distinct from conventional wound healing as tissue was regrown in response to a partial amputation as opposed to the closing up of an injury site with a scar of unknown tissue composition. Similar capabilities have been observed in whitespotted bamboo sharks ( Chiloscyllium plagiosum ) which can regenerate at least two thirds of their liver ( Lu et al, 2013 ) and many species of shark routinely regenerate and replace their teeth throughout their lives ( Rasch et al, 2016 ). Complete limb regeneration is a notable physiological adaptation in some higher vertebrate species, and serves as a mechanism to regain functional use of an appendage following amputation ( Han et al, 2005 ).…”

Dynamic miRNA expression patterns during retinal regeneration in zebrafish: Reduced dicer or miRNA expression suppresses proliferation of Müller Glia‐derived neuronal progenitor cells

“…Although the targets and the molecular pathways through which these miRNAs function during retinal regeneration is unknown, it is worth noting that some of these miRNAs have similar functions in other tissues. Previously, miR-142 was suggested to play a role in liver regeneration (Lu et al, 2013) and control the balance between mesenchymal progenitor cell proliferation and differentiation through regulating Wnt signaling (Carraro et al, 2014). This is of interest because Wnt signaling was previously shown to play an important role in M€ uller glia dedifferentiation and proliferation in the regenerating zebrafish retina (Ramachandran et al, 2011;Wan et al, 2012).…”