Genetics and Lineage-Specific Evolution of a Lethal Hybrid Incompatibility between Drosophila Mauritiana and Its Sibling Species

By Cattani, M. Victoria; Presgraves, Daven C. | Genetics, April 2009 | Go to article overview

Genetics and Lineage-Specific Evolution of a Lethal Hybrid Incompatibility between Drosophila Mauritiana and Its Sibling Species


Cattani, M. Victoria, Presgraves, Daven C., Genetics


ABSTRACT

The Dobzhansky-Muller model posits that intrinsic postzygotic reproductive isolation-the sterility or lethality of species hybrids-results from the evolution of incompatible epistatic interactions between species: favorable or neutral alleles that become fixed in the genetic background of one species can cause sterility or lethality in the genetic background of another species. The kind of hybrid incompatibility that evolves between two species, however, depends on the particular evolutionary history of the causative substitutions. An allele that is functionally derived in one species can be incompatible with an allele that is functionally derived in the other species (a derived-derived hybrid incompatibility). But an allele that is functionally derived in one species can also be incompatible with an allele that has retained the ancestral state in the other species (a derived-ancestral hybrid incompatibility). The relative abundance of such derived-derived vs. derived-ancestral hybrid incompatibilities is unknown. Here, we characterize the genetics and evolutionary history of a lethal hybrid incompatibility between Drosophila mauritiana and its two sibling species, D. sechellia and D. simulans. We show that a hybrid lethality factor(s) in the pericentric heterochromatin of the D. mauritiana X chromosome, hybrid lethal on the X (hlx), is incompatible with a factor(s) in the same small autosomal region from both D. sechellia and D. simulans, Suppressor of hlx [Su(hlx)]. By combining genetic and phylogenetic information, we infer that hlx-Su(hlx) hybrid lethality is likely caused by a derived-ancestral incompatibility, a hypothesis that can be tested directly when the genes are identified.

SPECIATION often involves the evolution of intrinsic postzygotic reproductive barriers-including the sterility and inviability of hybrids-that limit the potential for genetic exchange between populations or species (Dobzhansky 1937; Coyne and Orr 2004). Hybrid sterility and inviability in animals are usually caused by incompatible gene interactions: often functionally divergent genes from one species are incompatible with interacting genes from another species. Many studies have mapped such hybrid incompatibility genes to small chromosomal regions (Naveira and Fontdevila 1986; Pantazidis et al. 1993;Carvajal et al. 1996;Hollocher andWu1996;Trueet al. 1996; SawamuraandYamamoto 1997; Naisbit et al. 2002; Presgraves 2003; Tao et al. 2003; Slotman et al. 2004; Moyle and Graham 2005; Sweigartet al. 2006;MaslyandPresgraves2007;Good et al. 2008) and, in several cases, identified the causative genes. These studies reveal that hybrid incompatibilities can involve functionally divergent protein-coding genes (Ting et al. 1998; Barbash et al. 2003; Presgraves et al. 2003; Brideau et al. 2006; Mihola et al. 2009; Phadnis and Orr 2009; Tang and Presgraves 2009), chimeric duplicate genes (Wittbrodt et al. 1989), repetitive DNA (Sawamura and Yamamoto 1997), and gene movement (Masly et al. 2006).

However, none of these individual hybrid incompatibility loci causes sterility or inviability on its own. Rather, as Dobzhansky (1937) and Muller (1940, 1942) first explained, hybrid fitness problems must involve deleterious epistatic interactions that evolve as incidental by-products of divergence (seeOrr 1996). In the usual depiction of the so-called Dobzhansky-Muller model, an ancestral population with the two-locus genotype aabb splits into two geographically isolated lineages and each fixes new and different substitutions (yielding AAbb and aaBB lineages, respectively); when brought together in hybrids (AaBb), an incompatibility between these substitutions causes hybrid sterility or hybrid inviability (Figure 1A). Recent theory shows that the evolution of hybrid incompatibilities should follow some simple rules. For example, hybrid incompatibilities should be asymmetric (i.e., A is incompatible with B, but a should be compatible with b), should often be complex (i. …

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

Sign up now for a free, 1-day trial and receive full access to:

  • Questia's entire collection
  • Automatic bibliography creation
  • More helpful research tools like notes, citations, and highlights
  • Ad-free environment

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

Items saved from this article

This article has been saved
Highlights (0)
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.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this article

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

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 article

Genetics and Lineage-Specific Evolution of a Lethal Hybrid Incompatibility between Drosophila Mauritiana and Its Sibling Species
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?

Full screen

matching results for page

Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, 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."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

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

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.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.