A comparative review of intelectins

Abstract

Intelectin (ITLN) is a new type of glycan‐binding lectin. It has been demonstrated to agglutinate bacteria probably due to its carbohydrate‐binding capacity, suggesting its role in an innate immune response. It is involved not only in many physiological processes but also in some human diseases such as asthma, heart disease, inflammatory bowel disease, chronic obstructive pulmonary disease and cancer. Up to now, intelectin orthologs have been identified in placozoans, urochordatas, cephalochordates and several vertebrates, such as cyclostomata, fish, amphibians and mammals. Although the sequences of intelectins in different species are conserved, their expression patterns, quaternary structures and functions differ considerably among and within species. We summarize the evolution of the intelectin gene family, the tissue distribution, structure and functions of intelectins. We conclude that intelectin plays a role in innate immune response and there are still potential functions of intelectin awaiting discovery.

Serum amyloid A is a positive acute phase protein in Russian sturgeon challenged with Aeromonas hydrophila

“…This work analysed the potential of five proteins, described as APPs in some teleosts, and whose upregulation would strengthen natural defences making them good infection biomarkers 18,19 . These proteins were HEPC, HPX/ WAP65-2 and TRFE, which regulate iron availability in the blood contributing to limit pathogen establishment and multiplication 47,56,57,67 , and ITLN and SAA, which behave as soluble receptors for bacteria and might mediate their agglutination and/or opsonization 28,68,69 . The coding sequence of these putative APPs was not available in public databases at the beginning of this investigation, although various Acipenser transcriptomes were published in the last years.…”

“…Regarding ITLNs, the scenario is more complex because they belong to a family of X-type lectins, comprising various isoforms in vertebrates, including fish. Moreover, even ITLN amino acid sequences in different species are conserved their expression patterns and functions differ considerably among and within species 69 . In teleosts, the major family member expressed in the liver might be species-specific and has been only documented in a few fish species, such as D. rerio and Ictalurus punctatus.…”

130 years of Plant Lectin Research

“…A detailed discussion of lectins outside the plant world, is beyond the scope of this review. For more information on lectins from viruses, bacteria, fungi, algae, invertebrates and vertebrates, their molecular structures and biological importance we refer to several recent review papers [162][163][164][165][166][167][168][169][170][171].…”

Extensive variation in the mouse intelectin gene family: recent duplications, deletions and inactivating variants result in diversity in laboratory strains

“…Intelectins (intestinal lectins) are a family of calcium-dependent multimeric, secreted proteins that selectively bind microbial carbohydrates (1)(2)(3). In mammals, intelectins were initially identified in the mouse small intestine, but are found throughout vertebrates, and have a variety of roles including host-microbe interaction (3)(4)(5)(6)(7)(8)(9). In humans, there are two intelectin proteins intelectin-1 and intelectin-2, encoded by the genes ITLN1 and ITLN2 respectively, which are tandemly arranged on chromosome 1q23.…”

“…In humans, there are two intelectin proteins intelectin-1 and intelectin-2, encoded by the genes ITLN1 and ITLN2 respectively, which are tandemly arranged on chromosome 1q23. 3. Human ITLN1, also known as omentin-1, is expressed in visceral adipose as well as the intestine (1,(10)(11)(12).…”