Allele Dmel\bam^hs.PO

General Information
Symbol	Dmel\bam^hs.PO	Species	D. melanogaster
Name	heat shock construct of Ohlstein	FlyBase ID	FBal0065895
Feature type	allele	Associated gene	Dmel\bam

Allele class
Mutagen	in vitro construct - regulatory fusion
Recent Updates
Description	What does this section display? This section contains items that were added to this record for each release. It currently only tracks new links between this FlyBase report and other FlyBase data classes (e.g. genes, references, stocks) or controlled vocabulary terms (e.g. GO, anatomy terms). What does this section not display? This section does not currently display links that were removed or gene model changes.
Update Feed	Click the icon below to subscribe to this FlyBase record and receive updates automatically through your feed reader.
FB2013_03
FB2013_02
All updates	Click here to see a list of all updates to this record from FB2010_08 and on.
Nature of the Allele
Allele class
Mutagen	in vitro construct - regulatory fusion (Ohlstein and McKearin, 1997)
Mutations Mapped to the Genome

Type Location Additional Notes References
Associated Sequence Data
DDBJ / EMBL / GenBank	DNA sequence Protein sequence Name

UniProtKB/Swiss-Prot
UniProtKB/TrEMBL

Progenitor genotype
Nature of the lesion	Statement Reference Construct: A genomic fragment containing most of the bam transcription unit (including the entire open reading frame) and approximately 200bp 3' flanking sequences is expressed under the control of a heat shock promoter. (Ohlstein and McKearin, 1997)
Carried in construct	P{hs-bam.O} (Kai et al., 2005, Niki et al., 2006, Gilboa and Lehmann, 2004, Kai and Spradling, 2004, Casanueva and Ferguson, 2004, Kawase et al., 2004, Gilboa et al., 2003, Niki and Mahowald, 2003, Xie and Spradling, 2000, Lavoie et al., 1999, Morris et al., 2005, Szakmary et al., 2005, Ohlstein and McKearin, 1997, Parisi et al., 2001, Chen and McKearin, 2003, Kai and Spradling, 2003, Kirilly et al., 2005, Guo and Wang, 2009, Insco et al., 2009, Pek et al., 2009, Eliazer et al., 2011, Xia et al., 2010, Insco et al., 2012)
Cytology
Phenotypic Data
Phenotypic Class
	decreased cell number \| heat sensitive (Insco et al., 2009)
Phenotype Manifest In
	female germline stem cell (Xie and Spradling, 2000) female germline stem cell \| heat sensitive (Kai and Spradling, 2003) germarium (Ohlstein and McKearin, 1997) germarium & germ cell (Kirilly et al., 2005) germline cell (Lavoie et al., 1999) germline cell \| female \| larval stage \| heat sensitive (Gilboa and Lehmann, 2004) germline cyst \| ectopic \| heat sensitive (Gilboa and Lehmann, 2004) germline cyst \| heat sensitive (Kai and Spradling, 2004) male germline stem cell \| heat sensitive (Kawase et al., 2004) ovary (Ohlstein and McKearin, 1997) ovary \| larval stage \| heat sensitive (Kai and Spradling, 2004) spermatogonial cyst \| heat sensitive (Insco et al., 2009)
Detailed Description
	Statement Reference bam[hs.PO] males treated with heat-shock show premature differentiation of germline cysts at the 8-cell stage in 18% of cysts. bam[hs.PO] and wild-type flies raised without heat-shock produce no 8-cell cysts. (Insco et al., 2009) In bam^hs.PO females 10 days after two 2 hr heat shock treatments, no germ-line stem cells or their descendant are present in germaria. Somatic stem cell fill the stem cell niche, producing a bag of follicle cells. (Kirilly et al., 2005) 75% of larval ovaries in which bam^hs.PO is expressed using heat shock at the end of the first larval instar have many cysts, indicating premature differentiation of the primordial germ cells. Ovaries in which bam^hs.PO is expressed at the end of the second larval instar show differentiation of all primordial germ cells into cysts. Ovaries in which bam^hs.PO is expressed at the end of embryogenesis do not contain cysts. (Gilboa and Lehmann, 2004) When heat-shock is administered at the start of the second larval instar, 20 hours later, no single germ cells or cell pairs remain. Instead only 4 and 8-cell cysts are found in numbers that correspond closely to the starting number of single and transiently interconnected germ cell pairs, respectively. It seems that the differentiating germ cells revert to stem cells. The characteristic shape of the fusomes and appearance of ring canals in these larval cysts are indistinguishable from adult cysts. Over the next 20-30 hours of larval development, however, the cysts become unstable and begin to break down. By 50 hours after heat shock, only single cells are found in mutant ovaries. Apoptosis does not seem to be the cause of these phenotypes. The cysts appear to break into single cells by ring canal closure and fusome fragmentation. 50 hours after heat shock, ring canal remnants can be seen in the single germ cells. Adult females who have received heat treatment have normal numbers of wild type germ cell cysts. The environment surrounding the stem cells is indistinguishable from controls and constituted a normal niche. Five day old treated and control females lay normal eggs at about the same rate as controls. the reconstituted stem cells appear to have a normal half life. (Kai and Spradling, 2004) Two days after heat shock, the average number of germline stem cells per testis is reduced to 3.9 (compared to 9.3 in controls). A week after heat shock about 70% of the testes have no germline stem cells, with an average of 2 per testis, compared to 7.6 in controls. (Kawase et al., 2004) When animals are heatshocked at 37^oC for an hour, followed by an hour at 25^oC, and then another hour at 37^oC, the germ-line stem cells (GSCs) differentiate and exit the GSC niche within 24 hours. After 4 days, the youngest germ cells are in region 2b cysts, whereas after 7 days, the only germ cells remaining in the germarium are in a single stage-1 follicle. The terminal filament cells and cap cells (CpCs), remain stable for an extended period after the GSCs depart. Terminal filament cells change little for at least three weeks. Moreover CpCs appear normal even when all germ cells are gone 8-10 days after heat shock. However by 18 days after GSC loss, CpCs could no longer be detected. Inner-germarium sheath cells (IGSs) are much less stable, no IGSs are detected 8-9 days after ablation. The departure of germ cells and the death IGSs brings somatic stem cells (SSCs) increasingly closer to the GSC niche. Ectopic follicle cell progenitors divide within the vacated niche but IGSs do not. (Kai and Spradling, 2003) Over the course of several days after heat shock, bam^hs.PO germ cell stem cells (GSCs) are lost and all germ line cysts complete development and leave the germarium. Such germaria lose all inner germarium sheath cells (ISCs). In contrast terminal filament and cape cells do not change in the absence of germ cells. Somatic cells continue in their vicinity as in germaria that form in the presence of germ cells. Despite their presence near the GSC niche, these dividing somatic cells do not become GSCs. (Xie and Spradling, 2000) Overexpression of bam with P{hs-bam.O} causes germ cell loss. (Lavoie et al., 1999) Females carrying bam^hs.PO that are heat-shocked daily for 6 days have dramatically smaller ovaries than heat-shocked wild-type females. The ovarioles contain maturing egg chambers, but none are younger than stage 3 or 4. The germaria are shrunken. The germaria of females carrying bam^hs.PO that are 7 or more days post-heat shock appear to be completely devoid of germ cells, and are filled with a small number of squamous cells. Somatic stem cell populations are not affected by ectopic expression of bam^hs.PO. Ectopic expression of bam^hs.PO has no deleterious effects for male germline cells; heat-shocked males carrying bam^hs.PO are fertile and spermatogenesis appears normal. (Ohlstein and McKearin, 1997)
External Data
Linkouts
Interactions
	Show the genetic interaction network for Enhancers & Suppressors
Phenotypic Class
Phenotype Manifest In
Enhancer of
Statement Reference bam^hs.PO is an enhancer of germ cell & germarium phenotype of zpg^unspecified (Gilboa et al., 2003)
NOT Enhancer of
Statement Reference bam^hs.PO is a non-enhancer of egg chamber phenotype of aret^QB (Parisi et al., 2001)
Suppressor of
Statement Reference bam^hs.PO is a suppressor \| partially of egg chamber phenotype of twin^ry3 (Morris et al., 2005) bam^hs.PO is a suppressor \| partially of oocyte phenotype of twin^ry3 (Morris et al., 2005) bam^hs.PO is a suppressor of cystoblast phenotype of Scer\GAL4^{nos.UTR.T:Hsim\VP16}, tkv^{Q253D.Scer\UAS.P\T} (Casanueva and Ferguson, 2004) bam^hs.PO is a suppressor of egg chamber phenotype of Scer\GAL4^{nos.UTR.T:Hsim\VP16}, tkv^{Q253D.Scer\UAS.P\T} (Casanueva and Ferguson, 2004) bam^hs.PO is a suppressor of female germline stem cell \| ectopic phenotype of Scer\GAL4^{nos.UTR.T:Hsim\VP16}, tkv^{Q253D.Scer\UAS.P\T} (Casanueva and Ferguson, 2004) bam^hs.PO is a suppressor of male germline cell phenotype of mael^M391/Df(3L)79E-F (Pek et al., 2009) bam^hs.PO is a suppressor of ovary phenotype of Scer\GAL4^{nos.UTR.T:Hsim\VP16}, tkv^{Q253D.Scer\UAS.P\T} (Casanueva and Ferguson, 2004) bam^hs.PO is a suppressor of spermatogonial cyst \| supernumerary phenotype of Scer\GAL4^nos.PG, mir-7^Scer\UAS.cLb (Pek et al., 2009)
NOT Suppressor of
Statement Reference bam^hs.PO is a non-suppressor of egg chamber phenotype of aret^QB (Parisi et al., 2001) bam^hs.PO is a non-suppressor of germline cell phenotype of bgcn¹ (Lavoie et al., 1999)
Other
Statement Reference bam^hs.PO, gbb⁴/gbb^D4 has follicle cell & germarium \| conditional - heat sensitive phenotype (Kirilly et al., 2005) bam^hs.PO, gbb⁴/gbb^D4 has germarium \| heat sensitive phenotype (Kirilly et al., 2005) bam^hs.PO, gbb^D20/gbb⁴ has follicle cell & germarium \| conditional - heat sensitive phenotype (Kirilly et al., 2005) bam^hs.PO, gbb^D20/gbb⁴ has germarium \| heat sensitive phenotype (Kirilly et al., 2005) bam^hs.PO, zpg^unspecified has female germline stem cell phenotype (Gilboa et al., 2003, Gilboa et al., 2003) Scer\GAL4^C587, bam^hs.PO, dpp^Scer\UAS.cNa has germline cyst \| heat sensitive phenotype (Kai and Spradling, 2004, Kai and Spradling, 2004) Su(var)3-3^ΔN, bam^hs.PO has female germline cyst phenotype (Eliazer et al., 2011)
Additional Comments
Genetic Interactions
Statement Reference Expression of bam[hs.PO] in Su(var)3-3[ΔN] mutants results in the formation of multicellular cysts that contain branched fusomes indicating that Su(var)3-3[ΔN] mutant germline cells can undergo differentiation and formation of multicellular cysts. (Eliazer et al., 2011) The differentiation defects seen in the testes of mael[M391]/Df(3L)79E-F males are rescued by expression of bam[hs.PO]. The increase in the number of spermatogonial cysts per testis that is seen in males expressing mir-7[Scer\UAS.cLb] under the control of Scer\GAL4[nos.PG] is suppressed if they are also expressing bam[hs.PO]. (Pek et al., 2009) bam^hs.PO animals cultured at 18^oC and heat shocked as late stage pupae (37^oC, 4 times for 2 hours each with an 8-12 hour interval) produce adult females with agametic germaria. If these animals also carry the temperature sensitive allelic combination gbb⁴/gbb^D4 and are shifted to 29^oC (the non-permissive temperature) for 10 days, the majority of germaria disintegrate. Among remaining germaria, less than half contain follicle cells but all contain terminal filament cells. In identical experiments using gbb⁴/gbb^D20, no follicle cells remain, although the resulting germaria do contain terminal filament cells. In identical experiments using dpp^hr56/dpp^e90, the agametic germaria contain only slightly less follicle cells than controls (bam^hs.PO only). (Kirilly et al., 2005) The egg chamber defects seen in twin^ry3 hemizygotes at 25^oC are partly suppressed by expression of bam^hs.PO. (Morris et al., 2005) When bam^hs.PO is driven by heat shock in dpp^Scer\UAS.cNa, Scer\GAL4^C587 adults, cysts break down by a process of ring canal closure and fusome scission, de-differentiating. The multiple germ-line stem cells in each ovariole immediately and synchronously begin to differentiate after heat shock and soon generate 4-cell and 8-cell cysts. There are no single cells or cell pairs remaining at 20 h after heat shock. however by 30 h after heat shock (AHS) the cysts stop growing and start to beak down. By 40 h AHS closed ring canals and ring cell remnants are common. By 50 h AHS almost all germ cells are single. (Kai and Spradling, 2004) When bam^hs.PO, dpp^hr4/dpp^hr56, are heatshocked at 37^oC for an hour, followed by an hour at 25^oC, and then another hour at 37^oC then kept at the permissive temperature for 5 days and then shifted to 29^oC, follicle cell progenitors divide at the same rate as those cells without mutant dpp. When bam^hs.PO, hh^ts2, are heatshocked at 37^oC for an hour, followed by an hour at 25^oC, and then another hour at 37^oC then kept at the permissive temperature for 5 days and then shifted to 29^oC, follicle cell progenitors fail to divide. When bam^hs.PO, hh^hs.PI, are heatshocked at 37^oC for an hour, followed by an hour at 25^oC, and then another hour at 37^oC the follicle cell progenitors divide much more than those without hh^hs.PI. (Kai and Spradling, 2003) bam^Δ86 ovarian tumor cells transplanted into the dorsal mesoderm of stage 11-12 embryos from osk^unspecified mothers can repopulate the ovaries of the resulting adults, forming tumorous ovaries. The fertility of these flies can be rescued by heat shock if the transplanted cells carry bam^hs.PO. (Niki and Mahowald, 2003) Overexpression of bam with P{hs-bam.O} in a homozygous bgcn¹ mutant causes tumorous germ cells to develop, in which fusomes do not mature as normal (as for the bgcn¹ mutant alone). Germ line stem cells are not lost in the adults of these heat shocked P{hs-bam.O} homozygous bgcn¹ mutants, though they are eliminated in their bgcn¹/+ siblings. (Lavoie et al., 1999)
Xenogenetic Interactions
Statement Reference
Complementation & Rescue Data
Partially rescues	bam^hs.PO partially rescues bam^Δ86 (Ohlstein and McKearin, 1997)
Comments
Stocks ( 2 )
Bloomington	24636 P{hs-bam.O}18d, w¹¹¹⁸ 24637 w¹¹¹⁸; P{hs-bam.O}11d/TM3, Sb¹
Notes on Origin
Discoverer

External Crossreferences & Linkouts
Other Crossreferences

Linkouts

Synonyms & Secondary IDs ( 2 )
Reported As
Symbol Synonym	bam^hs.PO
Name Synonym	heat shock construct of Ohlstein (Ohlstein and McKearin, 1997)
Secondary FlyBase IDs

References ( 25 )

Generate a list of	All references relating to this allele ( 25 )

List References by type	Research paper ( 24 ) Supplementary material ( 1 )
Recent research papers ( 2 )
	Insco et al., 2012, Cell Stem Cell 11(5): 689--700 A self-limiting switch based on translational control regulates the transition from proliferation to differentiation in an adult stem cell lineage. [FBrf0219873] Eliazer et al., 2011, Proc. Natl. Acad. Sci. U.S.A. 108(17): 7064--7069 Loss of lysine-specific demethylase 1 nonautonomously causes stem cell tumors in the Drosophila ovary. [FBrf0213593] Show all research papers ...

Allele Dmel\bamhs.PO

Allele Dmel\bam^hs.PO