Working-for-Food Behaviors: A Preclinical Study in Prader-Willi Mutant Mice

By Lassi, Glenda; Maggi, Silvia et al. | Genetics, November 2016 | Go to article overview

Working-for-Food Behaviors: A Preclinical Study in Prader-Willi Mutant Mice


Lassi, Glenda, Maggi, Silvia, Balzani, Edoardo, Cosentini, Ilaria, Garcia-Garcia, Celina, Tucci, Valter, Genetics


(ProQuest: ... denotes formulae omitted.)

PRADER-WILLI syndrome (PWS) is a rare neurodevelopmental disorder that is caused by genomic imprinting defects within the small nuclear ribonucleoprotein N (SNPRN) cluster of the human chromosome region 15q1113. PWS is characterized by developmental delays, feeding problems, hyperphagia, behavioral disorders, and sleep-wake disturbances (Peters 2014; Tucci 2016). In preclinical investigations, mouse models with different deletions at the orthologous locus on mouse chromosome 7C have shown the main features of the human syndrome, such as growth retardation (Rozhdestvensky etal. 2016), hyperphagia (Davies etal. 2015), and sleep abnormalities (Lassietal. 2016). Small nucleolar RNA 116 (Snord116, also called MBII-85), a paternally expressed noncoding gene that modifies other small nuclear RNAs (snoRNAs), is considered one of the key players in PWS (Peters 2014). Expression studies of the snoRNAs MBI-36, MBII-85 (Snord116), MBII-52 (Snord115), and MBII-13 show that these snoRNAs are either exclusively or prevalently expressed in the brain (Cavaillé et al. 2000). Yet, it has been demonstrated that MBII-52, MBII-85, and MBII13 are imprinted in the mouse brain. However, no analysis of the imprinting status of Snord116 in different areas of the brain has yet been conducted. Mice that maternally inherit the Snord116 deletion are phenotypically similar to wild type (Skryabin et al. 2007); thus, the paternal inheritance of the mutation is the critical heterozygous pattern to be investigated. However, several studies have indicated that the investigation of homozygous mutants may also be needed to fully understand the role of Snord116 (Wolf et al. 2008; Qi et al. 2016). Biallelic deletion of Snord116 in mice produces classical developmental phenotypes associated with reduced body weight and growth; however, as mutant mice enter adulthood, hyperphagia is observed, and the balance between energy intake and expenditure is altered (Qi et al. 2016). The regulatory processes involved in maintaining body weight homeostasis through daily food intake and expenditure include a proper balance between thermoregulation and physiological states (Overton and Williams 2004; Florant and Healy 2012), and between behavior and cognitive processes (Chen et al. 2016; Higgs 2016). Recently, we studied the link between thermogenesis and sleep in PWScrm+/p2 mutant mice, reporting a significant increase in the circadian variations of body temperature that disrupt sleep in mutants (Lassi et al. 2016).The latter study suggests that Snord116 is involved in sleep-wake regulation, and in the daily control of body temperature. Thermogenesis plays an important role in adjusting metabolism both during sleep, when energy expenditure is reduced owing to resting, and during wakefulness, when the individual is searching for food and engaging in physical activity (Schmidt 2014). Food intake is governed by at least two important motivations, the need for calories, and the hedonic value of food (Challet and Mendoza 2010). However, food intake is also structured by fundamental cognitive/behavioral processes, such as clock-dependent mechanisms (Mistlberger 2011). By studying the PWSICdel mouse line, Davies et al (2015) reported that hyperphagia in these PWS mutant mice is due to a constant need for calories, and that the related behavior is not due to an increased hedonic value of food intake. In particular, the PWSICdel mice presented similar behavioral licking responses compared to control mice toward palatable food. That study concluded that the hyperphagic trait in mutant mice is due mainly to one of two motivational systems; it remains to be understood whether the specific need for calories influences behavioral or cognitive processes in mutants as they access food during the day. Therefore, here, we explored fundamental aspects of the behavioral and cognitive systems associated with food-intake (i.e., working-for-food behavioral strategies) in the mouse mutant model PWScrm+/p2 (Skryabin et al. …

The rest of this article is only available to active members of Questia

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA 8, MLA 7, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

(Einhorn 25)

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Note: primary sources have slightly different requirements for citation. Please see these guidelines for more information.

Cited article

Working-for-Food Behaviors: A Preclinical Study in Prader-Willi Mutant Mice
Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Help
Full screen
Items saved from this article
  • Highlights & Notes
  • Citations
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

matching results for page

    Questia reader help

    How to highlight and cite specific passages

    1. Click or tap the first word you want to select.
    2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
    3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

    OK, got it!

    Cited passage

    Style
    Citations are available only to our active members.
    Buy instant access to cite pages or passages in MLA 8, MLA 7, APA and Chicago citation styles.

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

    "Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

    1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

    Cited passage

    Thanks for trying Questia!

    Please continue trying out our research tools, but please note, full functionality is available only to our active members.

    Your work will be lost once you leave this Web page.

    Buy instant access to save your work.

    Already a member? Log in now.

    Search by... Author
    Show... All Results Primary Sources Peer-reviewed

    Oops!

    An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.