Sains Malaysiana 55(10)(2026): 1681-1689

http://doi.org/10.17576/jsm-2026-5510-07

 

SLIRP at the Interface of Mitochondrial RNA Homeostasis and Translation

(SLIRP pada Antara Muka Homeostasis dan Translasi RNA Mitokondria)

 

JINGUO CAO^1,#, YINING LI^1,#, XIAOHUI HU^2,# & JIANHONG TANG^1,3,*

 

¹Key Laboratory of Mitochondrial Medicine, Department of Basic Medicine, Gannan Medical University, Ganzhou, China

²Department of Basic Medicine, Gannan Healthcare Vocational College, Ganzhou, China

³Laboratory Animal Engineering Research Center of Ganzhou, Science Research Center, Gannan Medical University, Ganzhou, China

 

Received: 8 June 2026/Accepted: 11 September 2026

 

*Corresponding author; email: tangjianhong@gmu.edu.cn

 

#These authors contributed equally to this work

 

Abstract

Mitochondrial gene expression relies on precise coordination between RNA metabolism and protein synthesis, yet how these processes are functionally coupled remains incompletely understood. Stem-loop interacting RNA-binding protein (SLIRP), a conserved component of the LRPPRC-containing ribonucleoprotein complex, has emerged as a key factor in this process. While initially characterized as a stabilizer of mitochondrial mRNAs, accumulating structural, biochemical, and genetic evidence indicates that SLIRP primarily functions to coordinate mitochondrial translation. Rather than being required for transcript production, SLIRP ensures the efficient and selective utilization of mitochondrial mRNAs by the mito-ribosome, thereby maintaining ordered and productive protein synthesis. Disruption of SLIRP results in selective translational defects, tissue-specific vulnerability, and mitochondrial disease phenotypes, despite the persistence of mitochondrial transcripts. We propose a conceptual framework in which SLIRP acts at the interface between RNA homeostasis and translational output, integrating mitochondrial gene expression across molecular, cellular, and organismal scales.

Keywords: LRPPRC; mitochondria; protein translation; RNA homeostasis; SLIRP

Abstrak

Ekspresi gen mitokondria bergantung pada penyelarasan yang tepat antara metabolisme RNA dan sintesis protein, namun bagaimana kedua-dua proses ini digandingkan secara fungsian masih belum difahami sepenuhnya. Gelung batang yang berinteraksi dengan protein pengikat RNA (SLIRP), iaitu komponen terpelihara dalam kompleks ribonukleoprotein yang mengandungi LRPPRC, telah muncul sebagai faktor utama dalam proses ini. Walaupun pada awalnya dicirikan sebagai penstabil mRNA mitokondria, bukti struktur, biokimia dan genetik yang semakin bertambah menunjukkan bahawa SLIRP berfungsi terutamanya untuk menyelaraskan translasi mitokondria. Berbanding berperanan dalam penghasilan transkrip, SLIRP memastikan penggunaan mRNA mitokondria yang cekap dan selektif oleh mitoribosom, sekali gus mengekalkan sintesis protein yang tersusun dan produktif. Gangguan terhadap SLIRP mengakibatkan kecacatan translasi yang selektif, kerentanan tisu yang khusus dan fenotip penyakit mitokondria, walaupun transkrip mitokondria masih wujud. Kami mencadangkan satu kerangka konseptual bahawa SLIRP bertindak pada antara muka antara homeostasis RNA dan output translasi, dengan mengintegrasikan ekspresi gen mitokondria merentasi skala molekul, sel dan organisma.

Kata kunci: Homeostasis RNA; LRPPRC; mitokondria; SLIRP; translasi protein

 

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