Kin discrimination increases with genetic distance in a social amoeba.
Kin discrimination increases with genetic distance in a social amoeba.
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DOI：
10.1371/journal.pbio.0060287
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发表时间：
2008-11-25
期刊：
影响因子：
9.8
通讯作者：
Strassmann, Joan E.
中科院分区：
文献类型：
--
作者：
Ostrowski, Elizabeth A.;Katoh, Mariko;Shaulsky, Gad;Queller, David C.;Strassmann, Joan E.
在社会性变形虫盘基网柄菌中，数千个细胞在饥饿时聚集形成多细胞子实体，其中大约 20% 死亡形成茎，使其他细胞受益。多细胞发育的集体性质使得细胞很容易被作弊者利用，而且作弊的可能性确实很高。如果细胞能够区分个体并避开那些基因不同的个体，它们就可能避免成为受害者。我们通过混合来自覆盖其大部分自然范围的不同地区的分离株来测试社会变形虫的合作范围。我们在这里表明，不同的分离株在聚集过程中部分地相互排斥，并且这种排斥的程度与菌株之间的遗传距离之间存在正相关关系。我们的研究结果表明，与不同的个体相比，盘状 D. discoideum 细胞与遗传相似的个体之间的共聚集更多，这表明存在一种机制来辨别这种社会微生物中个体之间的遗传相似程度。在盘基网柄菌等社会性变形虫中，细胞聚集形成多细胞蛞蝓，该蛞蝓会迁移，然后形成子实体，其中含有活孢子（继续产生新的变形虫）和死亡的茎细胞。与所有细胞都来自同一个受精卵的动物不同，社会性阿米巴子实体可以含有不同基因型的细胞。这种嵌合现象的潜力产生了一个概念问题，即“作弊者”细胞可能会优先成为繁殖孢子，并迫使受害者成为茎细胞并死亡。变形虫可以避免被欺骗的一种方法是，它们识别并优先聚集基因相似的细胞，同时避开基因遥远的细胞——这一过程称为亲属歧视。我们测试了盘状 D. discoideum 细胞是否能够以这种方式进行区分。我们混合了来自遗传不同菌株的细胞，发现它们在多细胞发育过程中分离。分离程度随着菌株之间遗传距离的增加而逐渐增加。我们的结果表明，盘状 D. discoideum 存在亲属歧视，这种能力可能会降低作弊的可能性，并确保茎细胞的死亡为相关个体提供适应性优势。社会变形虫中基于基因的歧视可能有助于这些细胞避免利用其利他行为的作弊行为。
In the social amoeba Dictyostelium discoideum, thousands of cells aggregate upon starvation to form a multicellular fruiting body, and approximately 20% of them die to form a stalk that benefits the others. The aggregative nature of multicellular development makes the cells vulnerable to exploitation by cheaters, and the potential for cheating is indeed high. Cells might avoid being victimized if they can discriminate among individuals and avoid those that are genetically different. We tested how widely social amoebae cooperate by mixing isolates from different localities that cover most of their natural range. We show here that different isolates partially exclude one another during aggregation, and there is a positive relationship between the extent of this exclusion and the genetic distance between strains. Our findings demonstrate that D. discoideum cells co-aggregate more with genetically similar than dissimilar individuals, suggesting the existence of a mechanism that discerns the degree of genetic similarity between individuals in this social microorganism. In social amoebae such as Dictyostelium discoideum, cells aggregate to form a multicellular slug that migrates and then forms a fruiting body, which contains live spores (which go on to make new amoebae) and dead stalk cells. Unlike animals where all the cells descend from one fertilized egg, social amoeba fruiting bodies can contain cells with different genotypes. This potential for chimerism creates a conceptual problem in that “cheater” cells could arise that preferentially become reproductive spores and force the victims to become stalk cells and die. One way that amoebae could avoid being cheated is if they recognize and preferentially aggregate with genetically similar cells while avoiding genetically distant cells—a process called kin discrimination. We tested whether cells of D. discoideum could discriminate in this way. We mixed cells from genetically distinct strains and found that they segregate during multicellular development. The degree of segregation increases in a graded fashion with the genetic distance between strains. Our results demonstrate the existence of kin discrimination in D. discoideum, an ability that is likely to reduce the potential for cheating and ensure that the death of the stalk cells provides a fitness advantage to related individuals. Genetically based discrimination in social amoebae may help these cells to avoid cheaters that take advantage of their altruistic behavior.
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影响因子：
2
作者：
HAMILTON, WD
通讯作者：
HAMILTON, WD
DOI：
10.1073/pnas.0702723104
发表时间：
2007-05-22
影响因子：
11.1
作者：
Gilbert, Owen M.;Foster, Kevin R.;Queller, David C.
通讯作者：
Queller, David C.
DOI：
10.1073/pnas.91.8.3166
发表时间：
1994-04-12
影响因子：
11.1
作者：
DIRIENZO, A;PETERSON, AC;FREIMER, NB
通讯作者：
FREIMER, NB
影响因子：
16.8
作者：
Grosberg, RK;Strathmann, RR
通讯作者：
Strathmann, RR
影响因子：
4.9
作者：
Blouin, MS;Parsons, M;Lotz, S
通讯作者：
Lotz, S