Loss of the basic helix-loop-helix transcription factor Bhlhe41 induces cell death and impairs neurite outgrowth in Neuro2a cells
The basic helix-loop-helix (bHLH) superfamily of transcription factors have been implicated in a wide range of cellular functions such as proliferation, differentiation, tumorigenesis, and circadian rhythms. In a previous siRNA-based screen, bHLH family member e41 (BHLHE41) had been identified as a putative regulator of neuronal differentiation; however, its function remains largely elusive. To this end, using the CRISPR-Cas9 system, we established an isogenic Neuro2a (N2a) cell line with biallelic targeting of Bhlhe41 gene (Bhlhe41−/−). In undifferentiated N2a cells, complete knockout of Bhlhe41 resulted in marked proliferation inhibition, together with accumulation of apoptotic cells. Furthermore, retinoic acid (RA)-induced neurite outgrowth and expression of neuronal markers are significantly weakened in Bhlhe41−/− cells. We also showed that the activity of ERK1/2 signaling, a key regulator of neuronal differentiation, is likewise impaired in knockout cells. Together, these results suggest that Bhlhe41 plays critical roles in regulating cell death and neurite outgrowth in N2a cells.
KeywordsBhlhe41 Apoptosis Neurite outgrowth ERK1/2 signaling
This study was supported by National Natural Science Foundation of China (81201671) and Foundation of Science and Technology Department of Jilin Province (20180101306JC, 20180101144JC).
XL, YS, and HZ designed the project, contributed to all experiments and to writing the manuscript. YS, HZ, LW, JL, and HJ conducted the experiments. ZW and ST helped with cell culture. LQ helped with data collection and analysis. All authors read and provided their approval for the final version of the manuscript.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
The studies did not involve human participants or animals and therefore did not require ethical approval or informed consent to undertake.
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