A new study published in Nature Communications by researchers from the Human Protein Atlas presents a high-resolution spatial map of proteins associated with motile cilia in the human fallopian tube, providing new insights into reproductive biology, infertility and cilia-related disease. All data from the study are publicly available in the Tissue Resource of the Human Protein Atlas.

The fallopian tube plays a central role in human reproduction, where coordinated movement of motile cilia helps transport the egg, sperm and early embryo. Although disruptions in fallopian tube function are linked to infertility and disease, the protein landscape of this tissue has remained incompletely characterized.

In the new study, the researchers used an integrated transcriptomics and proteomics approach to identify genes and proteins with elevated expression in the fallopian tube. RNA-seq analysis revealed 310 fallopian tube-elevated genes, the majority associated with motile cilia function. Using validated antibodies and immunohistochemistry, the team then spatially mapped 133 corresponding proteins in the fallopian tube and other human tissues containing motile cilia, including respiratory, reproductive and brain tissues.

Most of the analyzed proteins were localized specifically to ciliated epithelial cells, and many could be assigned to distinct subcellular regions, such as the cilium, ciliary base, cytoplasm or nucleus. The results were further supported by single-cell RNA-seq and mass spectrometry data, creating a robust publicly available resource for exploring cilia biology at the protein level.

The study also identified several poorly characterized proteins with previously limited evidence in cilia databases. Eleven such proteins were further examined in tissue from a hydrosalpinx patient, a condition associated with fallopian tube obstruction and infertility. The hydrosalpinx sample showed a thinner epithelium, reduced abundance of FOXJ1-positive ciliated cells and decreased expression of the cilia-associated proteins FHAD1, RIIAD1 and C2orf81.

Together, the findings provide a detailed spatial reference map of cilia-associated proteins in the human fallopian tube and highlight candidate proteins that may be important for ciliary function, reproductive health and disease. By making the full dataset openly available through the Tissue Resource of the Human Protein Atlas, the study offers a valuable resource for future research on infertility, ciliopathies and fallopian tube-related disorders.