Functional Annotation of CH1 (Fel d 1 Chain 1) — UniProt P30438, *Felis catus* Falcon

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Functional Annotation of CH1 (Fel d 1 Chain 1) — UniProt P30438, Felis catus

Gene Identity and Nomenclature

The gene symbol CH1 in Felis catus (domestic cat) encodes chain 1 of the major allergen Fel d 1 (UniProt accession P30438). This protein is described as "Major allergen I polypeptide chain 1" and belongs to the secretoglobin family, featuring a characteristic uteroglobin domain. In the literature, the gene product is almost universally referred to as Fel d 1 rather than by the gene symbol CH1 (gronlund2010themajorcat pages 1-2). The functional protein Fel d 1 is a heterodimer comprising two distinct polypeptide chains: chain 1 (encoded by CH1) and chain 2 (encoded by CH2), which associate via three inter-chain disulfide bonds (gronlund2010themajorcat pages 1-2, popescu2021moleculardiagnosisin pages 2-4). This report describes the biology of the CH1 gene product in the context of the mature Fel d 1 complex.

The following table summarizes the key properties of the CH1/Fel d 1 gene product:

Property Summary Evidence
Protein name Fel d 1; major cat allergen; UniProt P30438 corresponds specifically to chain 1 of the Fel d 1 complex (major allergen I polypeptide chain 1). (gronlund2010themajorcat pages 2-3, gronlund2010themajorcat pages 1-2)
Gene names CH1 encodes chain 1; Fel d 1 is produced as a two-chain secretoglobin complex comprising chain 1 and chain 2, commonly discussed together as the CH1/CH2 gene product. (gronlund2010themajorcat pages 1-2, brackett2022newfrontiersprecise pages 3-4)
UniProt accession P30438 (chain 1 / CH1). (gronlund2010themajorcat pages 2-3, gronlund2010themajorcat pages 1-2)
Organism Felis catus (domestic cat). (popescu2021moleculardiagnosisin pages 2-4, satyaraj2019keepthecat pages 1-2)
Protein family Secretoglobin family; uteroglobin-like protein rather than a lipocalin; homologous to rabbit uteroglobin and human Clara cell protein/CC16. (popescu2021moleculardiagnosisin pages 2-4, gronlund2010themajorcat pages 2-3)
Molecular weight Acidic glycoprotein; apparent mass 35–39 kDa by size-exclusion chromatography; quaternary structure consists of two non-covalently linked ~18-kDa heterodimers. (gronlund2010themajorcat pages 1-2)
Structure: overall architecture Small tetrameric secretoglobin composed of two heterodimers; all-helical protein with 8 helices and an internal ligand-binding cavity; tetramer contains three calcium-binding sites. (gronlund2010themajorcat pages 2-3, popescu2021moleculardiagnosisin pages 2-4)
Structure: chain 1 Chain 1 is an ~8-kDa, 70-aa polypeptide; structurally similar to chain 2 despite limited sequence identity; chain 1 contains prominent T-cell epitopes and is the UniProt P30438 product. (gronlund2010themajorcat pages 1-2, gronlund2010themajorcat pages 3-3)
Structure: chain 2 Chain 2 is an ~10-kDa glycopeptide, covalently linked to chain 1 by three inter-chain disulfide bonds; carries the N-linked tri-antennary glycan; skin-associated form is ~90 aa and salivary-gland form ~92 aa. (gronlund2010themajorcat pages 1-2, popescu2021moleculardiagnosisin pages 2-4)
Ligands Binds fatty acids and steroids; reported optimal ligands include lauric acid and androsterone. Structural cavity is consistent with small hydrophobic ligand binding typical of secretoglobins. (popescu2021moleculardiagnosisin pages 2-4, karn2025abroadgenome pages 9-10)
Tissue expression sites Produced by sebaceous glands, salivary glands, lacrimal glands, anal sacs, and perianal glands; co-expressed in skin and salivary glands. (popescu2021moleculardiagnosisin pages 2-4, gronlund2010themajorcat pages 2-3, gronlund2010themajorcat pages 1-2, brackett2022newfrontiersprecise pages 2-3)
Expression/regulation Produced by all cats, but levels vary widely; expression is testosterone-regulated; intact males produce more Fel d 1, and neutering reduces production by roughly 3–5-fold. (popescu2021moleculardiagnosisin pages 4-5)
Biological function (putative) Native function in cats remains not definitively established. Evidence supports putative roles in epithelial/skin defense, immunoregulation, and intra-species chemical communication; ligand binding suggests a role in transport/presentation of hydrophobic signaling molecules. (popescu2021moleculardiagnosisin pages 2-4, gronlund2010themajorcat pages 2-3, brackett2022newfrontiersprecise pages 2-3)
Biochemical/immunological activity Experimentally shown to bind LPS and enhance TLR4 and TLR2 signaling via CD14/MD2-dependent lipid transfer, increasing innate immune activation; this is the best-defined molecular activity, though demonstrated mainly in the context of allergenicity rather than confirmed cat physiology. (herre2013allergensasimmunomodulatory pages 6-7, herre2013allergensasimmunomodulatory pages 1-2, herre2013allergensasimmunomodulatory pages 4-6, herre2013allergensasimmunomodulatory pages 10-14)
Subcellular localization Secreted extracellular protein localized to secretory epithelia and glandular secretions; deposited on skin, hair follicles, and fur during grooming; shed into the environment with hair and dander; present at high levels on fur, lower in saliva, and minimal in urine. (popescu2021moleculardiagnosisin pages 2-4, gronlund2010themajorcat pages 2-3, popescu2021moleculardiagnosisin pages 4-5)

Table: This table summarizes the verified identity, structure, ligands, expression, localization, and putative biological function of the Fel d 1 CH1/CH2 secretoglobin complex in domestic cats. It is useful as a compact reference for functional annotation of UniProt P30438/CH1 in the context of the full Fel d 1 heterotetramer.

Protein Structure

Primary and Quaternary Architecture

Fel d 1 is an acidic glycoprotein with an apparent molecular weight of 35–39 kDa by size-exclusion chromatography (gronlund2010themajorcat pages 1-2). The native protein is a tetramer consisting of two non-covalently linked ~18-kDa heterodimers. Each heterodimer contains two antiparallel polypeptide chains: chain 1 (~8 kDa, 70 amino acids) and chain 2 (~10 kDa), covalently linked by three inter-chain disulfide bonds (gronlund2010themajorcat pages 1-2). Chain 2 carries the glycan moiety of the protein, a complex N-linked tri-antennary carbohydrate structure accounting for 10–20% of the molecular weight (gronlund2010themajorcat pages 1-2). Despite only 10–15% sequence identity between chains 1 and 2, the two polypeptides are structurally similar (gronlund2010themajorcat pages 2-3).

Three-Dimensional Structure and Uteroglobin Fold

The crystal structure of Fel d 1, solved in 2003 by Kaiser et al., revealed an all-helical protein containing 8 helices with the characteristic uteroglobin (UG) fold — a four-helix bundle forming a boomerang-shaped structure (gronlund2010themajorcat pages 2-3). This fold is shared among all secretoglobin family members and creates a central hydrophobic cavity capable of harboring small ligands (gronlund2010themajorcat pages 2-3). Dimer formation generates two pockets of different sizes: a smaller 350-ų compartment and a larger 750-ų compartment, with the larger pocket formed by dislocation of amino acids creating a cavity entrance (gronlund2010themajorcat pages 2-3). The tetrameric form contains three well-defined calcium-binding sites, a feature consistent with other uteroglobin structures (gronlund2010themajorcat pages 2-3, gronlund2010themajorcat pages 3-3).

Chain 1 (the CH1 product, P30438) shares approximately 30% sequence identity with rabbit uteroglobin, while chain 2 shows lower (10–15%) sequence homology (gronlund2010themajorcat pages 2-3). Notably, Fel d 1 is distinguished from most other mammalian allergens in being a uteroglobin-like protein rather than a lipocalin (gronlund2010themajorcat pages 2-3, gronlund2010themajorcat pages 3-3). Chain 2 exists in tissue-specific isoforms: a shorter 90-amino acid version is preferentially found in skin, while a longer 92-amino acid version is expressed in salivary glands (gronlund2010themajorcat pages 1-2).

Biological Function

Native Function in the Cat

The precise biological function of Fel d 1 in cat physiology remains formally unestablished (popescu2021moleculardiagnosisin pages 2-4, gronlund2010themajorcat pages 2-3). However, converging lines of evidence suggest several putative roles:

  1. Lipid and steroid transport/presentation: Fel d 1 binds fatty acids and steroids, with lauric acid and androsterone identified as optimal ligands (popescu2021moleculardiagnosisin pages 2-4). This is consistent with the hydrophobic ligand-binding cavity characteristic of the secretoglobin fold, which in other family members (e.g., uteroglobin) binds progesterone and phospholipids (karn2025abroadgenome pages 9-10, karn2025abroadgenome pages 13-14). The production of Fel d 1 is under testosterone control, with intact male cats producing significantly more than castrated males, and this reduction being reversible by exogenous testosterone (popescu2021moleculardiagnosisin pages 4-5). These observations suggest a hormonal signaling or transport function.

  2. Intra-species chemical communication: The testosterone-dependent expression pattern, secretion by multiple exocrine glands, and ability to bind volatile steroids like androsterone suggest a role in pheromone-like chemical communication between cats (popescu2021moleculardiagnosisin pages 2-4). This is supported by evolutionary parallels: mouse salivary androgen-binding protein (ABP), another secretoglobin, functions in reproductive isolation and species recognition (karn2025abroadgenome pages 14-15).

  3. Epithelial defense and immunoregulation: Fel d 1 has been proposed to play a protective role for cat skin and may be involved in local immunoregulation (popescu2021moleculardiagnosisin pages 2-4, brackett2022newfrontiersprecise pages 2-3).

Immunomodulatory Activity: Lipid Transfer and TLR Enhancement

The best-characterized molecular activity of Fel d 1 was demonstrated by Herre et al. (2013), who showed that Fel d 1 functions as an immunomodulatory protein (IMP) that enhances innate immune signaling. Specifically, recombinant Fel d 1 increased LPS-induced TLR4 signaling approximately 15-fold in HEK293 cells and also enhanced TLR2 signaling in response to lipoteichoic acid (LTA), but did not modify TLR5 signaling (herre2013allergensasimmunomodulatory pages 4-6). The mechanism involves Fel d 1 directly binding lipopolysaccharide (LPS) and facilitating lipid transfer to CD14 and the TLR signaling complex, rather than acting as a co-receptor mimic like the dust mite allergen Der p 2 (herre2013allergensasimmunomodulatory pages 6-7, herre2013allergensasimmunomodulatory pages 1-2). Enhancement is dependent on both MD2 and CD14 co-receptors and is independent of glycosylation (herre2013allergensasimmunomodulatory pages 6-7). In primary macrophages and human PBMCs, Fel d 1 potentiated TNFα production in response to bacterial lipid ligands (LPS, LTA, Pam2CSK4, Pam3CSK4), with effects confirmed to operate through TLR4 by ablation in TLR4-deficient cells (herre2013allergensasimmunomodulatory pages 10-14). This lipid-binding and immunomodulatory activity explains, at least in part, the mechanism by which Fel d 1 promotes allergic sensitization in humans — by amplifying innate immune responses to environmental lipid pathogen-associated molecular patterns (PAMPs) at low concentrations (herre2013allergensasimmunomodulatory pages 14-17).

Evolutionary Context: The Secretoglobin Superfamily

Secretoglobins (SCGBs) are small, dimeric, cytokine-like proteins with a characteristic four-helix bundle (UG fold) and conserved ligand-binding residues (karn2025abroadgenome pages 4-6). A comprehensive genome survey by Karn and Laukaitis (2025) revealed that SCGBs are not uniquely mammalian but are widespread in amniotes, including turtles, crocodilians, lizards, and birds, suggesting their origin in the Carboniferous Period (~320 MYA) (karn2025abroadgenome pages 1-2). The family binds retinoids, phospholipids, steroids, and calcium (karn2025abroadgenome pages 1-2, karn2025abroadgenome pages 9-10). Uteroglobin (SCGB1A1), the prototypical family member, is induced by progesterone and secreted into reproductive and airway luminal fluid, where it binds sperm surface proteins and modulates motility (karn2025abroadgenome pages 9-10). Despite extensive research, no clear function has been established for any SCGB, though they are dysregulated in lung disease, kidney disease, inflammation, and cancer (karn2025abroadgenome pages 2-4). The deep evolutionary conservation and functional diversity of SCGBs strongly suggest a fundamental, yet poorly characterized, biological role common to all amniotes (karn2025abroadgenome pages 1-2).

Strikingly, the brachial gland exudate secretion protein (BGEsp) of slow lorises (Nycticebus spp.) — a 17.6-kDa secretoglobin heterodimer — shows strong structural homology to Fel d 1 rather than to primate proteins, representing an unusual case of convergent evolution between lorises and felids (fitzpatrick2023slowlymakingsense pages 7-8). In lorises, this secretoglobin participates in a two-step venom system with functions in ectoparasite defense and intraspecific competition, and may also serve as an olfactory chemical signal (fitzpatrick2023slowlymakingsense pages 11-13, fitzpatrick2023slowlymakingsense pages 22-23). This convergence further supports the hypothesis that Fel d 1 may play roles in chemical communication and defense in cats.

Tissue Expression and Localization

Fel d 1 is a secreted extracellular protein produced by multiple glandular tissues in cats. Production sites include sebaceous glands, salivary glands, lacrimal glands, anal sacs, and perianal glands (popescu2021moleculardiagnosisin pages 2-4, brackett2022newfrontiersprecise pages 2-3). Chain 1 and chain 2 are co-expressed in both skin and salivary glands, though with tissue-specific chain 2 length variants (gronlund2010themajorcat pages 1-2). The allergen is deposited onto skin, hair follicles, and fur during grooming, and is subsequently shed into the environment with hair and dander (popescu2021moleculardiagnosisin pages 2-4, gronlund2010themajorcat pages 2-3). Levels on fur are highest at the neck region (ranging from 1 to 1,770 μg/g), with lower levels in saliva and minimal concentrations in urine (popescu2021moleculardiagnosisin pages 4-5).

All cats produce Fel d 1 regardless of breed, age, hair length, sex, or housing conditions, but individual variation is substantial — up to an 80-fold difference in salivary Fel d 1 levels between cats (satyaraj2019keepthecat pages 1-2). Production is androgen-regulated: intact male cats produce 3–5 times more Fel d 1 than neutered males, and this reduction can be reversed by exogenous testosterone administration (popescu2021moleculardiagnosisin pages 4-5). Urine is not a significant source, though hormonal status affects urinary levels in intact male cats (popescu2021moleculardiagnosisin pages 4-5). Once shed, Fel d 1 becomes airborne as particles from dried saliva and dandruff, and is passively transferred to environments lacking cats (homes, vehicles, public buildings) on clothing (gronlund2010themajorcat pages 2-3, satyaraj2019keepthecat pages 1-2).

Allergenicity and Clinical Significance

Fel d 1 accounts for 60–96% of cat dander's allergenic activity, with approximately 88–96% of IgE responses to cat allergens directed against Fel d 1, and roughly 95% of cat-allergic patients producing IgE antibodies to this protein (popescu2021moleculardiagnosisin pages 4-5, brackett2022newfrontiersprecise pages 3-4, gronlund2010themajorcat pages 3-3). It is the immunodominant allergen in cat allergy, which affects approximately 1 in 5 adults worldwide (satyaraj2019keepthecat pages 1-2). A recent comprehensive study by Trifonova et al. (2023) confirmed that Fel d 1, along with Fel d 4 and Fel d 7, was recognized by more than 65% of patients with respiratory allergy to cats, and induced basophil degranulation at hundred-fold lower concentrations than other cat allergens (trifonova2023allergenicactivityof pages 1-2, trifonova2023allergenicactivityof pages 15-16).

Recent Developments and Therapeutic Approaches

Several innovative strategies are being pursued to reduce Fel d 1 exposure or mitigate its allergenic effects:

  1. CRISPR gene editing: Brackett et al. (2022) demonstrated CRISPR-based knockout of CH1 and CH2 genes in feline kidney epithelial cells with editing efficiencies of 5–55%, with no off-target mutations detected (brackett2022newfrontiersprecise pages 3-4). This approach aims to create hypoallergenic cats by eliminating Fel d 1 at the genetic source (brackett2022newfrontiersprecise pages 1-2).

  2. Anti-Fel d 1 antibody approaches: Polyclonal anti-Fel d 1 antibodies delivered through cat food achieved a 47% reduction in haircoat allergen levels, while immunization of cats with anti-Fel d 1 resulted in approximately 50% reduction in tear extract allergen and 30% reduction in allergic patient symptoms (brackett2022newfrontiersprecise pages 2-3).

  3. Recombinant IgG4 therapy: Passive immunization of cat-allergic patients using Fel d 1-specific recombinant human IgG4 antibodies has been demonstrated to be clinically effective (trifonova2023allergenicactivityof pages 1-2).

  4. Hypoallergen design: Engineered Fel d 1 variants with disrupted disulfide bridges show 400–900 times lower IgE-binding capacity while preserving T-cell activation, serving as candidates for allergen-specific immunotherapy (gronlund2010themajorcat pages 5-6).

  5. Peptide immunotherapy: Second-generation vaccines consisting of overlapping T-cell epitope peptides demonstrated reduced late-phase skin reactions, decreased allergen-stimulated proliferation, and increased IL-10 production (gronlund2010themajorcat pages 5-6).

Summary

The CH1 gene in Felis catus encodes chain 1 of Fel d 1, a secreted secretoglobin protein with the characteristic uteroglobin fold. The mature Fel d 1 is a tetrameric heterodimer complex with an internal hydrophobic cavity that binds fatty acids (lauric acid) and steroids (androsterone). While its native biological function in cats is not definitively established, evidence supports roles in lipid transport/presentation, chemical communication, and epithelial defense, consistent with the broader secretoglobin family. Its best-characterized molecular activity is the enhancement of TLR4/TLR2 innate immune signaling through lipid binding and transfer — a property that underlies its exceptional allergenicity in humans. Fel d 1 is produced by multiple exocrine glands under testosterone regulation and is deposited onto cat fur and subsequently dispersed into the environment. It is the dominant allergen in cat allergy, recognized by over 90% of sensitized patients, and is the target of emerging genetic, immunological, and pharmacological strategies to reduce allergen exposure.

References

  1. (gronlund2010themajorcat pages 1-2): Hans Grönlund, Tiiu Saarne, Guro Gafvelin, and Marianne van Hage. The major cat allergen, fel d 1, in diagnosis and therapy. International Archives of Allergy and Immunology, 151:265-274, Oct 2010. URL: https://doi.org/10.1159/000250435, doi:10.1159/000250435. This article has 154 citations and is from a peer-reviewed journal.

  2. (popescu2021moleculardiagnosisin pages 2-4): Florin-Dan Popescu, Carmen Saviana Ganea, Carmen Panaitescu, and Mariana Vieru. Molecular diagnosis in cat allergy. World Journal of Methodology, 11:46-60, May 2021. URL: https://doi.org/10.5662/wjm.v11.i3.46, doi:10.5662/wjm.v11.i3.46. This article has 35 citations.

  3. (gronlund2010themajorcat pages 2-3): Hans Grönlund, Tiiu Saarne, Guro Gafvelin, and Marianne van Hage. The major cat allergen, fel d 1, in diagnosis and therapy. International Archives of Allergy and Immunology, 151:265-274, Oct 2010. URL: https://doi.org/10.1159/000250435, doi:10.1159/000250435. This article has 154 citations and is from a peer-reviewed journal.

  4. (brackett2022newfrontiersprecise pages 3-4): Nicole F. Brackett, Anna Pomés, and Martin D. Chapman. New frontiers: precise editing of allergen genes using crispr. Frontiers in Allergy, Jan 2022. URL: https://doi.org/10.3389/falgy.2021.821107, doi:10.3389/falgy.2021.821107. This article has 40 citations and is from a peer-reviewed journal.

  5. (satyaraj2019keepthecat pages 1-2): Ebenezer Satyaraj, Harold James Wedner, and Jean Bousquet. Keep the cat, change the care pathway: a transformational approach to managing fel d 1, the major cat allergen. Allergy, 74:5-17, Sep 2019. URL: https://doi.org/10.1111/all.14013, doi:10.1111/all.14013. This article has 103 citations and is from a highest quality peer-reviewed journal.

  6. (gronlund2010themajorcat pages 3-3): Hans Grönlund, Tiiu Saarne, Guro Gafvelin, and Marianne van Hage. The major cat allergen, fel d 1, in diagnosis and therapy. International Archives of Allergy and Immunology, 151:265-274, Oct 2010. URL: https://doi.org/10.1159/000250435, doi:10.1159/000250435. This article has 154 citations and is from a peer-reviewed journal.

  7. (karn2025abroadgenome pages 9-10): Robert C Karn and Christina M Laukaitis. A broad genome survey reveals widespread presence of secretoglobin genes in squamate and archosaur reptiles that flowered into diversity in mammals. Genome Biology and Evolution, Feb 2025. URL: https://doi.org/10.1093/gbe/evaf024, doi:10.1093/gbe/evaf024. This article has 0 citations and is from a domain leading peer-reviewed journal.

  8. (brackett2022newfrontiersprecise pages 2-3): Nicole F. Brackett, Anna Pomés, and Martin D. Chapman. New frontiers: precise editing of allergen genes using crispr. Frontiers in Allergy, Jan 2022. URL: https://doi.org/10.3389/falgy.2021.821107, doi:10.3389/falgy.2021.821107. This article has 40 citations and is from a peer-reviewed journal.

  9. (popescu2021moleculardiagnosisin pages 4-5): Florin-Dan Popescu, Carmen Saviana Ganea, Carmen Panaitescu, and Mariana Vieru. Molecular diagnosis in cat allergy. World Journal of Methodology, 11:46-60, May 2021. URL: https://doi.org/10.5662/wjm.v11.i3.46, doi:10.5662/wjm.v11.i3.46. This article has 35 citations.

  10. (herre2013allergensasimmunomodulatory pages 6-7): Jurgen Herre, Hans Grönlund, Heather Brooks, Lee Hopkins, Lisa Waggoner, Ben Murton, Monique Gangloff, Olaniyi Opaleye, Edwin R. Chilvers, Kate Fitzgerald, Nick Gay, Tom Monie, and Clare Bryant. Allergens as immunomodulatory proteins: the cat dander protein fel d 1 enhances tlr activation by lipid ligands. The Journal of Immunology, 191:1529-1535, Aug 2013. URL: https://doi.org/10.4049/jimmunol.1300284, doi:10.4049/jimmunol.1300284. This article has 131 citations.

  11. (herre2013allergensasimmunomodulatory pages 1-2): Jurgen Herre, Hans Grönlund, Heather Brooks, Lee Hopkins, Lisa Waggoner, Ben Murton, Monique Gangloff, Olaniyi Opaleye, Edwin R. Chilvers, Kate Fitzgerald, Nick Gay, Tom Monie, and Clare Bryant. Allergens as immunomodulatory proteins: the cat dander protein fel d 1 enhances tlr activation by lipid ligands. The Journal of Immunology, 191:1529-1535, Aug 2013. URL: https://doi.org/10.4049/jimmunol.1300284, doi:10.4049/jimmunol.1300284. This article has 131 citations.

  12. (herre2013allergensasimmunomodulatory pages 4-6): Jurgen Herre, Hans Grönlund, Heather Brooks, Lee Hopkins, Lisa Waggoner, Ben Murton, Monique Gangloff, Olaniyi Opaleye, Edwin R. Chilvers, Kate Fitzgerald, Nick Gay, Tom Monie, and Clare Bryant. Allergens as immunomodulatory proteins: the cat dander protein fel d 1 enhances tlr activation by lipid ligands. The Journal of Immunology, 191:1529-1535, Aug 2013. URL: https://doi.org/10.4049/jimmunol.1300284, doi:10.4049/jimmunol.1300284. This article has 131 citations.

  13. (herre2013allergensasimmunomodulatory pages 10-14): Jurgen Herre, Hans Grönlund, Heather Brooks, Lee Hopkins, Lisa Waggoner, Ben Murton, Monique Gangloff, Olaniyi Opaleye, Edwin R. Chilvers, Kate Fitzgerald, Nick Gay, Tom Monie, and Clare Bryant. Allergens as immunomodulatory proteins: the cat dander protein fel d 1 enhances tlr activation by lipid ligands. The Journal of Immunology, 191:1529-1535, Aug 2013. URL: https://doi.org/10.4049/jimmunol.1300284, doi:10.4049/jimmunol.1300284. This article has 131 citations.

  14. (karn2025abroadgenome pages 13-14): Robert C Karn and Christina M Laukaitis. A broad genome survey reveals widespread presence of secretoglobin genes in squamate and archosaur reptiles that flowered into diversity in mammals. Genome Biology and Evolution, Feb 2025. URL: https://doi.org/10.1093/gbe/evaf024, doi:10.1093/gbe/evaf024. This article has 0 citations and is from a domain leading peer-reviewed journal.

  15. (karn2025abroadgenome pages 14-15): Robert C Karn and Christina M Laukaitis. A broad genome survey reveals widespread presence of secretoglobin genes in squamate and archosaur reptiles that flowered into diversity in mammals. Genome Biology and Evolution, Feb 2025. URL: https://doi.org/10.1093/gbe/evaf024, doi:10.1093/gbe/evaf024. This article has 0 citations and is from a domain leading peer-reviewed journal.

  16. (herre2013allergensasimmunomodulatory pages 14-17): Jurgen Herre, Hans Grönlund, Heather Brooks, Lee Hopkins, Lisa Waggoner, Ben Murton, Monique Gangloff, Olaniyi Opaleye, Edwin R. Chilvers, Kate Fitzgerald, Nick Gay, Tom Monie, and Clare Bryant. Allergens as immunomodulatory proteins: the cat dander protein fel d 1 enhances tlr activation by lipid ligands. The Journal of Immunology, 191:1529-1535, Aug 2013. URL: https://doi.org/10.4049/jimmunol.1300284, doi:10.4049/jimmunol.1300284. This article has 131 citations.

  17. (karn2025abroadgenome pages 4-6): Robert C Karn and Christina M Laukaitis. A broad genome survey reveals widespread presence of secretoglobin genes in squamate and archosaur reptiles that flowered into diversity in mammals. Genome Biology and Evolution, Feb 2025. URL: https://doi.org/10.1093/gbe/evaf024, doi:10.1093/gbe/evaf024. This article has 0 citations and is from a domain leading peer-reviewed journal.

  18. (karn2025abroadgenome pages 1-2): Robert C Karn and Christina M Laukaitis. A broad genome survey reveals widespread presence of secretoglobin genes in squamate and archosaur reptiles that flowered into diversity in mammals. Genome Biology and Evolution, Feb 2025. URL: https://doi.org/10.1093/gbe/evaf024, doi:10.1093/gbe/evaf024. This article has 0 citations and is from a domain leading peer-reviewed journal.

  19. (karn2025abroadgenome pages 2-4): Robert C Karn and Christina M Laukaitis. A broad genome survey reveals widespread presence of secretoglobin genes in squamate and archosaur reptiles that flowered into diversity in mammals. Genome Biology and Evolution, Feb 2025. URL: https://doi.org/10.1093/gbe/evaf024, doi:10.1093/gbe/evaf024. This article has 0 citations and is from a domain leading peer-reviewed journal.

  20. (fitzpatrick2023slowlymakingsense pages 7-8): Leah Lucy Joscelyne Fitzpatrick, Rodrigo Ligabue-Braun, and K. Anne-Isola Nekaris. Slowly making sense: a review of the two-step venom system within slow (nycticebus spp.) and pygmy lorises (xanthonycticebus spp.). Toxins, 15:514, Aug 2023. URL: https://doi.org/10.3390/toxins15090514, doi:10.3390/toxins15090514. This article has 8 citations.

  21. (fitzpatrick2023slowlymakingsense pages 11-13): Leah Lucy Joscelyne Fitzpatrick, Rodrigo Ligabue-Braun, and K. Anne-Isola Nekaris. Slowly making sense: a review of the two-step venom system within slow (nycticebus spp.) and pygmy lorises (xanthonycticebus spp.). Toxins, 15:514, Aug 2023. URL: https://doi.org/10.3390/toxins15090514, doi:10.3390/toxins15090514. This article has 8 citations.

  22. (fitzpatrick2023slowlymakingsense pages 22-23): Leah Lucy Joscelyne Fitzpatrick, Rodrigo Ligabue-Braun, and K. Anne-Isola Nekaris. Slowly making sense: a review of the two-step venom system within slow (nycticebus spp.) and pygmy lorises (xanthonycticebus spp.). Toxins, 15:514, Aug 2023. URL: https://doi.org/10.3390/toxins15090514, doi:10.3390/toxins15090514. This article has 8 citations.

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