Gene Loss

Publication Details

Identifier: JB_BKMDT3

Curator: Bernardo Pinto

DOI: 10.1007/s00239-023-10118-z

PMID: 37249590

Title:

Decay of Skin-Specific Gene Modules in Pangolins.

Abstract:

The mammalian skin exhibits a rich spectrum of evolutionary adaptations. The pilosebaceous unit, composed of the hair shaft, follicle, and the sebaceous gland, is the most striking synapomorphy. The evolutionary diversification of mammals across different ecological niches was paralleled by the appearance of an ample variety of skin modifications. Pangolins, order Pholidota, exhibit keratin-derived scales, one of the most iconic skin appendages. This formidable armor is intended to serve as a deterrent against predators. Surprisingly, while pangolins have hair on their abdomens, the occurrence of sebaceous and sweat glands is contentious. Here, we explore various molecular modules of skin physiology in four pangolin genomes, including that of sebum production. We show that genes driving wax monoester formation, Awat1/2, show patterns of inactivation in the stem pangolin branch, while the triacylglycerol synthesis gene Dgat2l6 seems independently eroded in the African and Asian clades. In contrast, Elovl3 implicated in the formation of specific neutral lipids required for skin barrier function is intact and expressed in the pangolin skin. An extended comparative analysis shows that genes involved in skin pathogen defense and structural integrity of keratinocyte layers also show inactivating mutations: associated with both ancestral and independent pseudogenization events. Finally, we deduce that the suggested absence of sweat glands is not paralleled by the inactivation of the ATP-binding cassette transporter Abcc11, as previously described in Cetacea. Our findings reveal the sophisticated and complex history of gene retention and loss as key mechanisms in the evolution of the highly modified mammalian skin phenotypes.

Last update:

25-04-2024

Associated Glosses (50 results)

GlossID	Species	Symbol	Gene Loss Mechanism	Loss Type	Lineage Specific	Citation
GL_RBOIH1	Phataginus tricuspis	AWAT2	LOF (frameshift, premature stop, ss)	Full	No	10.1007/s00239-023-10118-z
GL_SL3JNM	Manis crassicaudata	DGAT2L6	LOF (frameshift, premature stop, ss)	Full	Manis	10.1007/s00239-023-10118-z
GL_STFRBO	Manis pentadactyla	FABP9	LOF (frameshift, premature stop, ss)	Full	Pholidota	10.1007/s00239-023-10118-z
GL_TH1NDQ	Manis javanica	TCHHL1	LOF (frameshift, premature stop, ss)	Full	Manis	10.1007/s00239-023-10118-z
GL_WC2VGR	Manis pentadactyla	GSDMC	LOF (frameshift, premature stop, ss)	Full	Manis	10.1007/s00239-023-10118-z
GL_WYE0DR	Manis crassicaudata	GSDMA	Exon(s) deletion	Full	Manis	10.1007/s00239-023-10118-z
GL_X7ZYW9	Manis pentadactyla	GSDMD	Exon(s) deletion	Full	Pholidota	10.1007/s00239-023-10118-z
GL_XKFED7	Manis javanica	GSDMB	LOF (frameshift, premature stop, ss)	Full	Manis	10.1007/s00239-023-10118-z
GL_YGOIBS	Phataginus tricuspis	AWAT1	LOF (frameshift, premature stop, ss)	Full	Pholidota	10.1007/s00239-023-10118-z
GL_YSZCVJ	Manis crassicaudata	AADACL3	Other	Undetermined	No	10.1007/s00239-023-10118-z