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Iborra-Pernichi, M.

Publications and source records attributed to Iborra-Pernichi, M..

2 recordsLinked to original sources

Mitochondria-Lysosomes Crosstalk Shapes Neonatal Metabolic Transition in Neonatal Enterocytes

The neonatal gastrointestinal tract mediates nutrient absorption and the establishment of immune tolerance to commensal microbiota. In early life, lysosome-rich enterocytes (LREs) in the ileum are necessary for the intracellular digestion of maternal milk proteins. However, the molecular mechanisms sustaining their function remain incompletely characterized. Here, we demonstrate that LRE mitochondrial homeostasis and autophagic capacity are critical for efficient nutrient uptake and maintenance of their specialized identity, as disruption of either process leads to premature differentiation into post-weaning enterocytes (PECs) with diminished endolysosomal and metabolic activity. Transcriptomic profiling further revealed that neonatal LREs exhibit a distinctive antioxidant signature, which preserves redox balance and safeguards the expression of the transcriptional regulators MAFB and BLIMP1, both central repressors of the neonatal-to-adult metabolic transition. These findings establish the mitochondria-lysosome axis as a key determinant of LRE function and neonatal metabolic programming. They also provide a mechanistic framework for understanding how organelle dysfunction and redox imbalance may contribute to early-life malnutrition syndromes, such as Kwashiorkor, and suggest therapeutic strategies aimed at preserving mitochondrial and lysosomal integrity.

developmental biology↗

Diacylglycerol kinase zeta dictates CD40-mediated immune synapse formation, mTORC1 signaling and plasma cell fate in B lymphocytes

To mount a robust T-dependent immune response, antigen-specific B lymphocytes require CD40 stimulation through immune synapse formation with CD4+ T follicular helper cells. CD40 triggers the activation of mammalian target of rapamycin complex-1 (mTORC1) and remodels the mitochondria to meet increased bioenergetic and anabolic demands. We show that diacylglycerol-kinase-{zeta} (DGK{zeta}) has a crucial role in activating the mTORC1 pathway and remodeling mitochondria downstream of CD40 signaling in B cells. DGK{zeta} governs organelle translocation to the CD40-mediated immune synapse and the recruitment of mTORC1 to lysosomes. DGK{zeta}-/- B cells exhibited impaired mitochondria function, protein biosynthesis, metabolite transporter expression and cell cycle progression, accompanied by dysregulation of the transcriptional network governing B cell fate. These defects lead to a blockage in the progression of the germinal center response and plasma cell differentiation in vivo. Our findings establish DGK{zeta} as a key mediator of CD40 functions in the B cell response.

immunology↗