SEXUALLY DIMORPHIC EXPRESSION OF ANDROGEN RECEPTORS IN THE FETAL SHEEP ADRENAL GLAND

Sexual dimorphism occurs where different sexes of the same species display differences in characteristics not limited to reproduction. For the nematode Caenorhabditis elegans, in which the complete neuroanatomy has been solved for both hermaphrodites and males, sexually dimorphic features have been observed both in terms of the number of neurons and in synaptic connectivity. In addition, male behaviours, such as food-leaving to prioritise searching for mates, have been attributed to neuropeptides released from sex-shared or sex-specific neurons. In this study, we show that the lury-1 neuropeptide gene shows a sexually dimorphic expression pattern; being expressed in pharyngeal neurons in both sexes but displaying additional expression in tail neurons only in the male. We also show that lury-1 mutant animals show sex differences in feeding behaviours, with pharyngeal pumping elevated in hermaphrodites but reduced in males. LURY-1 also modulates male mating efficiency, influencing motor events during contact with a hermaphrodite. Our findings indicate sex-specific roles of this peptide in feeding and reproduction in C. elegans, providing further insight into neuromodulatory control of sexually dimorphic behaviours.

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Sexually dimorphic expression of sexual differentiation genes in the internal genital organs of Japanese quail embryos

General and Comparative Endocrinology ◽

10.1016/j.ygcen.2021.113917 ◽

2021 ◽

pp. 113917

Author(s):

Shinji Tsukahara ◽

Masahiro Morishita ◽

Shiho Sasaki ◽

Kanta Wakayama ◽

Kaito Kobayashi ◽

...

Keyword(s):

Japanese Quail ◽

Sexual Differentiation ◽

Sexually Dimorphic ◽

Sexually Dimorphic Expression ◽

Dimorphic Expression

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Sexually dimorphic expression of myosin heavy chains in the adult mouse masseter

Journal of Applied Physiology ◽

10.1152/jappl.2000.89.1.251 ◽

2000 ◽

Vol 89 (1) ◽

pp. 251-258 ◽

Cited By ~ 67

Author(s):

Jane M. Eason ◽

Gail A. Schwartz ◽

Grace K. Pavlath ◽

Arthur W. English

Keyword(s):

Adult Mouse ◽

Fiber Type ◽

Masticatory Muscles ◽

Sexually Dimorphic ◽

Heavy Chains ◽

Tissue Sections ◽

Type Composition ◽

Sexually Dimorphic Expression ◽

Dimorphic Expression

Little is known regarding the role of androgenic hormones in the maintenance of myosin heavy chain (MHC) composition of rodent masticatory muscles. Because the masseter is the principal jaw closer in rodents, we felt it was important to characterize the influence of androgenic hormones on the MHC composition of the masseter. To determine the extent of sexual dimorphism in the phenotype of masseter muscle fibers of adult (10-mo-old) C57 mice, we stained tissue sections with antibodies specific to type IIa and IIb MHC isoforms. Females contain twice as many fibers containing the IIa MHC as males, and males contain twice as many fibers containing the IIb MHC as females. There is a modest amount of regionalization of MHC phenotypes in the mouse masseter. The rostral portions of the masseter are composed mostly of type IIa fibers, whereas the midsuperficial and caudal regions contain mostly type IIb fibers. Using immunoblots, we showed that castration results in an increase in the expression of type IIa MHC fibers in males. Ovariectomy has no effect on the fiber type composition in females. We conclude that testosterone plays a role in the maintenance of MHC expression in the adult male mouse masseter.

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