Search bioRxiv⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/315739

Identification of TEX101 functional interactome through proteomic measurement of human spermatozoa homozygous for the missense variant rs35033974

Schiza, C.·Korbakis, D.·Jarvi, K.·Diamandis, E. P.·Drabovich, A. P.
View original source ↗Export metadata ↓

Abstract

TEX101 is a testis-specific cell-surface protein expressed exclusively in the male germ cells and a validated biomarker of male infertility. Mouse TEX101 was found essential for male fertility, and was suggested to function as a cell surface chaperone involved in maturation of proteins required for sperm migration and sperm-oocyte interaction. However, the precise functional role of human TEX101 is not known and cannot be studied in vitro due to the lack of human germ cell lines. Here, we genotyped 386 healthy fertile men and sub-fertile patients for a common and potentially deleterious missense variant rs35033974 of TEX101, and identified 52 heterozygous and 4 homozygous patients. We then discovered by targeted proteomics that the variant allele rs35033974 was associated with near-complete degradation (>97%) of the corresponding G99V TEX101 form, and suggested that spermatozoa of homozygous patients could serve as a knockdown model to study TEX101 function in humans. Differential proteomic profiling with label-free quantification measured 8,046 proteins in spermatozoa of eight men and identified 8 cell-surface and 9 secreted testis-specific proteins significantly down-regulated in four patients homozygous for rs35033974. Substantially reduced levels of testis-specific cell-surface proteins potentially involved in sperm migration and sperm-oocyte fusion (including LY6K and ADAM29) were confirmed by targeted proteomics and western blotting assays. Since recent population-scale genomic data revealed homozygous fathers with biological children, rs35033974 is not a single pathogenic factor of male infertility in humans. However, median TEX101 levels in seminal plasma were found 5-fold lower (P=0.0005) in heterozygous than in wild-type men of European ancestry. We conclude that spermatozoa of rs35033974 homozygous men have substantially reduced levels of TEX101 and could be used as a model to elucidate the precise TEX101 function, which will advance biology of human reproduction.\n\nNon-standard abbreviations

Source connections

Explore related subjects

molecular biologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Schiza, C., Korbakis, D., Jarvi, K., Diamandis, E. P., Drabovich, A. P.. 2018-05-07. Identification of TEX101 functional interactome through proteomic measurement of human spermatozoa homozygous for the missense variant rs35033974. https://doi.org/10.1101/315739

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Single-probe, high-yield spatial mapping of diverse short RNA motifs

Spatial transcriptomics has revolutionized our understanding of RNA biology. Hybridization-based methods map mRNA transcripts by tiling multiple labeled probes along each molecule to generate a visible fluorescent signal, restricting applicability to long transcripts. Short RNA motifs, consequently, can only accommodate a single probe and remain a spatially invisible dimension of RNA biology. Here we present SMOOTHY-FISH, a single probe strategy that directly visualizes short RNA motifs at the single-molecule resolution. By optimizing probe brightness, binding specificity, and target accessibility, our single ~20-nucleotide probe reached the practical ceiling of hybridization-based detection. We quantitatively mapped previously inaccessible short motifs - splice-isoform junctions, individual microRNAs, and structural conformations - in single cells and mouse brain tissues, each validated against orthogonal methods. This unveiled biological phenomena that were previously unknown: ratios of alternatively spliced isoforms are tightly regulated across cell populations, subcellular miRNA fractions are precisely maintained, and a designed RNA structure was found to have a prominent alternative conformation. These findings demonstrate that short RNA motifs possess key spatial information that has yet to be discovered. With SMOOTHY-FISH's optimized single probe technique, short RNA motifs are converted into a new routinely measurable axis of spatial transcriptomics.

molecular biology↗
bioRxiv2026

Comparative profiling of sperm small RNAs in cnidarians highlights potential for paternal inheritance

Small RNAs in mature sperm are crucial regulators of gene expression following fertilization during early development in bilaterians. However, the presence and functions of sperm-derived small RNAs remain poorly understood in early-diverging (i.e., non-bilaterian) metazoans. In this study, we characterize three classes of small RNAs-microRNAs (miRNAs), piwi-interacting RNAs (piRNAs), and tRNA-derived RNAs (tDRs)-in sperm from three phylogenetically and ecologically distinct species from the early-diverging phylum Cnidaria: the sea anemone Nematostella vectensis, the temperate stony coral Astrangia poculata, and the reef-building tropical coral Acropora hyacinthus. All three classes of small RNAs examined were present in sperm from these cnidarians. Most miRNAs were species-specific; however, target prediction analysis revealed enriched putative targets involved in conserved developmental and signaling pathways. piRNAs overlapped with transposable elements and genic regions, indicating a potential dual role in genomic maintenance and gene expression regulation. Characterization of tDRs demonstrated that 5 prime-terminal fragments constituted the primary structural type across the three species, driven by high accumulation of specific isoacceptors including 5 prime-tDR-GlyGCC. Together, these findings provide the first evidence that cnidarian sperm carry a rich repertoire of small RNAs, including both conserved and species-specific types. Their presence suggests that paternal small RNAs contribute important regulatory information to the zygote in cnidarians, implicating paternal small RNAs as possible mediators of epigenetic inheritance in this early-branching metazoan phylum.

molecular biology↗
bioRxiv2026

Aging activates latent enhancers that can be reversed withexercise

Aging profoundly alters the genome's regulatory landscape, but the properties of age-acquired enhancers, including how they are selected and sustained in aged animals are unclear. We used single-cell multiomics in the mouse heart to identify age-responsive cis-regulatory elements and endurance exercise to understand which of these elements can be attenuated. Aging increased AP-1 engagement at more than 100,000 regulatory loci across cardiac cell types. Exercise opposed most of these gains. Despite low endogenous accessibility, age-gained enhancer sequences drove reporter activity comparable to stable elements, revealing substantial latent transcriptional potential. Local sequence features distinguished responsiveness to aging and exercise. Reporter perturbations implicated sequence outside the AP-1 core, and mutagenesis localized informative positions to dispersed segments of dynamic enhancers. These enhancers were IL-1-sensitive and were preferentially responsive to neutralization of the cytokine in vivo. AP-1 inhibition further opposed age-associated transcription. Together, these findings support a model in which aging engages latent cell-type specific enhancers that are sustained in an active state by ongoing trans signaling. Aging therefore changes the deployment of existing regulatory information, while the acquired activity remains responsive to changes in signaling even in old age.

molecular biology↗