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_NBWITW	Manis pentadactyla	DGAT2L6	LOF (frameshift, premature stop, ss)	Full	Manis	10.1007/s00239-023-10118-z
GL_NBWWKO	Manis pentadactyla	GSDMA	Exon(s) deletion	Full	Manis	10.1007/s00239-023-10118-z
GL_NON3ON	Manis crassicaudata	AWAT1	Other	Undetermined	No	10.1007/s00239-023-10118-z
GL_O28Z8A	Manis javanica	AADACL3	LOF (frameshift, premature stop, ss)	Full	Pholidota	10.1007/s00239-023-10118-z
GL_OYTFM0	Phataginus tricuspis	TCHHL1	Gene deletion	Full	No	10.1007/s00239-023-10118-z
GL_PDCYCF	Manis javanica	GSDMD	Exon(s) deletion	Full	Pholidota	10.1007/s00239-023-10118-z
GL_Q32ZSQ	Manis javanica	GSDMA	Exon(s) deletion	Full	Manis	10.1007/s00239-023-10118-z
GL_QCAPVP	Manis crassicaudata	GSDMB	LOF (frameshift, premature stop, ss)	Full	Manis	10.1007/s00239-023-10118-z
GL_QSZRSO	Manis javanica	EDA2R	LOF (frameshift, premature stop, ss)	Full	Manis	10.1007/s00239-023-10118-z
GL_QTFPNK	Manis crassicaudata	TCHHL1	LOF (frameshift, premature stop, ss)	Full	Manis	10.1007/s00239-023-10118-z