Chicken GHR natural antisense transcript regulates GHR mRNA in LMH cells.

Li Zhang,Fengfang Qiu,Xiquan Zhang,Qinghua Nie,Dexiang Zhang,Qingbin Luo,Ting Li,Shudai Lin,Lilong An,Rumin Jia,Jinge Ma,Zhang Wang

doi:10.18632/oncotarget.12437

Abstract

Growth hormone receptor (GHR) played key roles in human and animal growth. Both human laron type dwarfism and sex linked dwarf chicken were caused by the mutation of GHR gene. In this study, we identified an endogenously expressed long non-coding natural antisense transcript, GHR-AS, which overlapped with the GHR mRNA (GHR-S) in a tail to tail manner. Spatial and temporal expression analyses indicated that GHR-AS were highly expressed in chicken liver and displayed ascending with the development of chicken from E10 to 3 w of age. Interfering GHR-AS caused GHR-S decreasing, accompanied with increasing of the inactive gene indicator, H3K9me2, in the GHR-S promoter regions in LMH cells. RNase A experiment exhibited that GHR-AS and GHR-S can form double strand RNAs at the last exon of GHR gene in vivo and in vitro, which hinted they could act on each other via the region. In addition, the levels of GHR-S and GHR-AS can be affected by DNA methylation. Compared the normal chicken with the dwarfs, the negative correlation trends were showed between the GHR-S promoter methylation status and the GHR-AS levels. This is the first report of that GHR gene possessed natural antisense transcript and the results presented here further highlight the fine and complicated regulating mechanism of GHR gene in chicken development.

Highlights

The natural occurred antisense transcripts (Nats), widely transcribed in human and animals, usually interacted with the sense RNA via their complemented regions [1, 2] and involved in various biological processes [3, 4], development and diseases [5], suggesting critical roles of antisense transcripts in mammalian gene expression
We identified an endogenously expressed long non-coding natural antisense transcript, Growth hormone receptor (GHR)-AS, which overlapped with the GHR mRNA (GHR-S) in a tail to tail manner
To verify that GHR-AS was an antisense RNA transcribed from the opposite strand of GHR gene in chicken liver, by designing biotin-labeled sense or antisense probe, we conducted northern blot

Summary

Introduction

The natural occurred antisense transcripts (Nats), widely transcribed in human and animals, usually interacted with the sense RNA via their complemented regions [1, 2] and involved in various biological processes [3, 4], development and diseases [5], suggesting critical roles of antisense transcripts in mammalian gene expression. A lot of Nats have been reported playing important roles in human diseases and mammalian development, such as Tsix [4], DHRS4-AS [3] and AS-IL1α [11]. Growth hormone receptor played key roles in human and animal growth. Both human laron type dwarfism [15] and sex linked dwarf chicken [16] were caused by the mutation of GHR gene. Previous studies revealed that chicken GHR gene possessed several kinds of sense transcripts by alternatively using different 5′UTR and other ways [17, 18]

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Results

Conclusion