EVALUATION OF THE EFFECT OF THE EXPRESSION INDUCTION OF TMEM 121 GENE ON Y1 CELLS VIABILITY, PROPAGATION AND MIGRATION

Abstract

Transmembrane Protein 121 (TMEM121) is spatially expressed in the adrenal capsule which considers a niche for stem/progenitor cells. Yet its biological function remains enigmatic. Overall studies present a dilemma, due to conflicting evidence suggesting TMEM121 may act as either a tumor suppressor or an oncogenic driver. To present a relative resolve to this ambiguity, this study was designed to speculate TMEM121 role in cell division and migration by inducing its expression in a mouse adrenocortical Y1 cell model. The current study employed computerized time-lapse microscopy following the induced expression of TMEM121 and its effect on cellular kinetics. A pIRES2-EGFP vector system was generated by cloning the TMEM121 coding sequence into this vector prior to transfection into Y1 cells. The transfected cells were then monitored over a 40-hour period to quantify the cellular key metrics. The results revealed that TMEM121 acts as a significant negative regulator of Y1 cell behavior (p < 0.01). Following transfection, a significant reduction in viable cell counts relative to controls was recorded (p < 0.05). However, this suppressive effect proved transient, because the continuous monitoring revealed the inhibition was later subsided, and cell viability converged with control levels within seven days, showing a non-significant difference from the control group. In terms of propagation, the expression of TMEM121 exerted a potent anti-proliferative effect; quantitative analysis showed a marked suppression in population doubling (p < 0.01), with the propagation index (60%) lower than the control group. The current study also observed that TMEM121 significantly impaired cell motility (p < 0.01) with approximately over 60% reduction. The behavioral motility of the TMEM12 transfected cells record lower directional persistence (p < 0.01), often pivoting in place rather than progressing linearly. This might occurs due to the potential downregulation of the PI3K/AKT signaling pathway, which is crucial for cytoskeletal remodeling which might be correlated with TMEM121 expression induction.