Allelic diversities in rice starch biosynthesis lead to a diverse array of rice eating and cooking qualities

涓浗绉戝闄㈤櫌澹潕瀹舵磱棰嗗鐨勭爺绌跺洟闃�12鏈�14鏃ュ湪鏂颁竴鏈熺編鍥姐�婂浗瀹剁瀛﹂櫌闄㈠垔銆嬶紙PNAS锛変笂鍙戣〃璁烘枃璇达紝浠栦滑鍙戠幇骞惰В鏋愪簡鍐冲畾绋荤背椋熺敤鍜岃捀鐓搧璐ㄧ殑鍩哄洜璋冩帶缃戠粶銆傝繖涓�鐮旂┒鎴愭灉灏嗘湁鍔╀簬寮�鍙戝彛鎰熸洿濂界殑绋荤背鍝佺銆� 绋荤背鏄汉绫荤殑閲嶈涓婚锛屽洜姝ゆ敼鑹ɑ绫抽鐢ㄥ搧璐ㄥ叿鏈夐噸瑕佹剰涔夈�傜瀛︾晫姝ゅ墠宸插彂鐜帮紝绋荤背鐨勯鐢ㄥ拰钂哥叜鍝佽川涓昏鐢辩洿閾炬穩绮夊惈閲忋�佽兌绋犲害銆佺硦鍖栨俯搴﹀喅瀹氾紝浣嗗涓婅堪鎬х姸鍙戞尌浣滅敤鐨勫垎瀛愭満鍒跺苟涓嶆竻妤氥�備负姝わ紝涓闄㈤仐浼犱笌鍙戣偛鐢熺墿瀛︾爺绌舵墍銆佷腑鍥芥按绋荤爺绌舵墍鍜屾壃宸炲ぇ瀛︾爺绌朵汉鍛樹互鍙婄編鍥藉牚钀ㄦ柉宸炵珛澶у鐨勪腑鍥界睄鐮旂┒浜哄憳鍦ㄥ垎瀛愭按骞充笂瀵硅繖涓�鏈哄埗杩涜浜嗗垎鏋愩��

鍦ㄥ巻鏃�7骞寸殑鐮旂┒涓紝鐮旂┒浜哄憳鍒╃敤鍊欓�夊熀鍥犲叧鑱斿垎鏋愭硶鍜屽垎瀛愰仐浼犲鍙戠幇浜�18涓笌绋荤背娣�绮夊悎鎴愮浉鍏冲熀鍥犵殑鐩镐簰浣滅敤锛屼互鍙婄敱姝ゆ瀯鎴愮殑璋冩帶绋荤背椋熺敤鍜岃捀鐓搧璐ㄧ殑绮剧粏缃戠粶锛屼粠鑰屽湪鍒嗗瓙姘村钩涓婃彮绀轰簡鐩撮摼娣�绮夊惈閲忋�佽兌绋犲害銆佺硦鍖栨俯搴︾殑鐩稿叧鎬с�佸喅瀹氳繖3涓�х姸鐨勪富鏁堝熀鍥犲拰寰晥鍩哄洜鍙婂畠浠箣闂寸殑浣滅敤鍏崇郴銆傜爺绌朵汉鍛樿繕杩涗竴姝ラ�氳繃杞熀鍥犲疄楠岃瘉瀹炰簡浠栦滑鐨勫彂鐜般��

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鈭� 浠ヤ笂杞嚜http://www.sciencenet.cn/htmlnews/2009/12/226178.shtm

1. Mapping and validation of quantitative trait loci for spikelets per panicle and 1,000-grain weight in rice (Oryza sativa L.).聽 [涓嬭浇]

姣忕棰栨暟鍜屽崈绮掗噸鐨凲TL

2. Dissection of a QTL reveals an adaptive, interacting gene complex associated with transgressive variation for flowering time in rice.聽 [涓嬭浇]

QTL鍒嗘瀽鎻ず鎺у埗姘寸ɑ寮�鑺辨椂闂寸殑鍩哄洜澶嶆潅浜掍綔鈥︹��

1. Vacuolar processing enzyme plays an essential role in the crystalline structure of glutelin in rice seed. <鏈帓鐗�>

VPE娑叉场鍔犲伐閰讹紵鍚笂鍘绘尯鐔熸倝鈥︹��

2. Knockdown of OsDCL2 in Rice Negatively Affects Maintenance of the Endogenous dsRNA Virus, Oryza sativa endornavirus. <鏈帓鐗�>

OsDCL2锛屽叧浜庡皬RNA鐨勶紝娌″叴瓒ｇ殑鏃犺鍚с��

3. PANICLE PHYTOMER2 (PAP2), encoding a SEPALLATA subfamily MADS-box protein, positively controls spikelet meristem identity in rice. <鏈帓鐗�>

PAP2锛屾帶鍒剁鍒嗗寲鐨勪竴鍩哄洜锛孧ADS-box铔嬬櫧銆�

The origin and evolution of fragrance in rice (Oryza sativa L.). [涓嬭浇]

Thanks to kunshanyu锛�鍏充簬杩欎釜鏂囩尞闆嗘潫(鐚涘嚮鎴�)涓竴绡囨枃绔犵殑璇︾粏銆�

杩欑瘒鏂囩珷鏄浗闄呮按绋绘墍鍜屽悍濂堝皵鐨勪竴涓ぇ鐗汼usan R. McCouch鍙戠殑锛屾嵁璇碨usan R. McCouch浠ュ墠鏄鏂囧鐨勶紝鎵�浠ュス鐨勬枃绔犲啓寰楅兘寰堥閫革紝鍛靛懙銆備粬浠�氳繃瀵归鍛虫湁鍏崇殑涓�涓富瑕佸熀鍥燽etaine aldehyde dehydrogenase gene (BADH2)鐨�8涓笉鍚宎lleles鐨勮繘鍖栧垎鏋愶紝鍙戠幇棣欏懗鍩哄洜鏈�鏃╁嚭鐜颁簬绮崇ɑ锛岃繖涓鐐瑰ぇ澶ф寫鎴樹簡浠ュ墠棣欑背浠庣奔绋昏捣婧愮殑鍋囪锛屽叿浣撳唴瀹硅鏂囩珷銆傞檮涓奻aculty1000鐨勮瘎璁哄涓嬶細

Starch Degradation

鍓嶅嚑骞寸殑缁艰堪浜� 鐮旂┒瀵硅薄涓昏鏄嫙鍏拌姤锛屽彾鐗囦腑鐨勬穩绮夐檷瑙AHWAY锛屼篃鍒嗘瀽浜嗗拰浼犵粺鐨勬穩绮夊偍钘忓櫒瀹樿儦涔充腑PATHWAY鐨勫紓鍚�

杩戞湡瀵规嫙鍏拌姤鍙剁墖澶滈棿娣�绮夐檷瑙ｇ爺绌惰〃鏄庤繖绫婚�斿緞鍜屾暀绉戜功涓婄殑妯″紡宸埆杩樻槸姣旇緝澶х殑锛岃櫧鐒舵湁浜涢�斿緞宸茬粡鐭ラ亾锛屼絾浠嶆湁璁稿鏈夊緟鐮旂┒銆傛潵鑷穩绮夐绮掔殑钁¤仛绯栫敱尾锛嶆穩绮夐叾姘磋В鎴愰害鑺界硸骞惰緭鍑哄彾缁夸綋銆傚湪缁嗚優璐ㄤ腑锛岄害鑺界硸鏄痶ransglucosylation鍙嶅簲鐨勫熀璐紝鐢熸垚钁¤悇绯杇lucose 鍜� glucosylated 鍙椾綋鍒嗗瓙銆傛槸浣曠閰舵敾鍑绘穩绮変綋鐢熸垚钁¤仛绯栵紝鐢熸垚浣曠鍙椾綋鍒嗗瓙杩樹笉鐭ラ亾銆傛嫙鍏拌姤鍙剁墖鐨勫厜鍚堝櫒瀹樹腑娣�绮夌殑鐬椂绉疮鍙婂叾閫斿緞鍦ㄥ叾浠栫墿绉嶄腑涔熼�傜敤锛屼絾瀵逛簬璋风被鐨勮儦涔冲拰璞嗙被鐨勬灉瀹炴潵璇存穩绮夌Н绱ā寮忚繕鏄紶缁熼�斿緞锛岃繖绡囨枃绔犱篃闃愯堪浜嗕笉鍚屼綋绯讳箣闂寸殑鍏宠仈鍜屽尯鍒��

Recent research reveals that starch degradation in Arabidopsis leaves at night is significantly different from the 鈥渢extbook鈥� version of this process.Although parts of the pathway are now understood, other parts remain to be discovered. Glucans derived from starch granules are hydrolyzed via 尾-amylase to maltose, which is exported from the chloroplast. In the cytosol maltose is the substrate for a transglucosylation reaction, producing glucose and a glucosylated acceptor molecule. The enzyme that attacks the starch granule to release glucans is not known, nor is the nature of the cytosolic acceptor molecule. An Arabidopsis-type pathway may operate in leaves of other species, and in nonphotosynthetic organs that accumulate starch transiently. However, in starchstoring organs such as cereal endosperms and legume seeds, the process differs from that in Arabidopsis and may more closely resemble the textbook pathway. We discuss the differences in relation to the biology of each system.

A novel superior factor widely controlling the rice grain quality

from Tokyo University of Science etc.

鑳氫钩鐨勭敓鎴愯繃绋嬩富瑕佸寘鎷偍钘忔穩绮夌殑鍚堟垚鍜岃泲鐧界殑绉疮銆� 杩欎竴杩囩▼褰撳彈鍒伴伃閬囬�嗗鑳佽揩鏃朵緥濡傞珮娓╀細鏀跺埌寮虹儓褰卞搷锛屽洜姝わ紝鍏ㄧ悆姘斿�欏彉鏆栫殑瓒嬪娍浼氬椋熺墿鐨勪骇閲忎骇鐢熸瀬澶у▉鑳� 銆傛穩绮夊悎鎴愬拰铔嬬櫧璐棌閫斿緞涓殑閰剁被鐩镐簰浣滅敤锛岀敓鎴愭按绋昏儦涔筹紝浣嗗叾璋冩帶鏈虹悊杩樹笉鏄庝簡銆傛湰鐮旂┒鍙戠幇浜嗕竴涓柊鐨勮皟鎺у瓙OsCEO1,浣滅敤鏄儦涔冲湪鐏屾祮鏃舵湡鐨勫紩瀵间綋銆俧lo锛�2鐨勮〃鍨嬬被浼间簬鍙楀埌楂樻俯褰卞搷鐨勪骇鐢熺殑绮夎川鎬х姸锛岃鏄庤繖涓�鍩哄洜瀵归珮娓╄儊杩晱鎰� 銆傚flo2鍥句綅鍏嬮殕鍒扮殑OsCEO1涓庡凡鐭ョ殑鍔熻兘鍩哄洜閮戒笉瀛樺湪鍚屾簮鎬э紝瀹冨睘浜庝竴涓潪淇濆畧鐨勫熀鍥犲鏃忥紝缂栫爜1720涓皑鍩洪吀锛屽寘鍚竴涓笁瑙掑洓鑲介噸澶嶅尯锛圱PR锛夛紝鍙兘鍙備笌铔嬬櫧浜掍綔銆傞叺姣嶅弻鏉傛壘鍑�1涓湭鐭ョ殑鏅氭湡鑳氳儙鍙戣偛鍚屾簮铔嬬櫧鍙�1涓亣瀹歨elix-loop-helix铔嬬櫧浣滅敤OsCEO1鐨勭洿鎺ヤ簰浣滃璞★紝缁撴灉涓苟娌℃湁涓庢穩绮夎泲鐧借串钘忓悎鎴愮浉鍏崇殑閰剁被锛岃�屽湪flo2绐佸彉浣撲腑锛屽緢澶氳繖绫荤殑閰讹紝涓昏鏄亣瀹氱殑璋冩帶铔嬬櫧锛岃〃杈句笂閮戒笅璋冦�傛�讳箣锛岀爺绌惰〃鏄庯紝OsCEO1鍙兘鍦ㄦ暣涓儦涔崇敓鎴愰�斿緞鐨勪笂娓歌皟鎺э紝骞跺楂樻俯鑳佽揩鐨勫搷搴旇捣鐫�閲嶈浣滅敤銆�

Synthesis of storage starch and protein accumulation is the main action of endosperm organogenesis in term of the economic importance of rice. This event is strongly disturbed by abiotic stresses such as high temperature; thus, the upcoming global warming will cause a crisis with a great impact on food production1,2. The enzymes for the protein storage and starch synthesis pathway should work in concert to carry out the organogenesis of rice endosperm3鈥�5, but the regulatory mechanism is largely unknown. Here we show that a novel regulatory factor, named OsCEO1, acts as the conductor of endosperm organogenesis during the rice grain filling stage. The physiological properties of floury-endosperm-2 (flo2) mutants showed many similarities to symptoms of grains developed under high-temperature conditions, suggesting important roles of the responsible gene in sensitivity to high-temperature stress. Our map-based cloning identified the responsible gene for the flo2 mutant, OsCEO1, which has no homology to any genes of known function. The OsCEO1 belongs to a novel conserved gene family and encodes a protein composed of 1,720 amino acid residues containing a TPR(tetratricopeptide repeat) motif, which is considered to mediate a protein-protein interaction. The yeast two-hybrid analysis raised an unknown protein showing homology to a late embryogenesis abundant protein and a putative basic helix-loop-helix protein as candidates for the direct interactor for OsCEO1, whereas no enzyme genes for the synthesis of storage substances were detected. The flo2 mutant exhibited reduced expression of several genes for putative regulatory proteins as well as many enzymes involved in storage starch and proteins. These results suggest that OsCEO1 is a superior conductor of the novel regulatory cascade of endosperm organogenesis and may have important roles in the response to high-temperature stress.

Overexpression of BiP has inhibitory effects on the accumulation of seed storage proteins in endosperm cells of rice聽 [涓嬭浇]

璐棌铔嬬櫧鍦ㄧ瀛愭垚鐔熻繃绋嬩腑鐗瑰紓澶ч噺鍚堟垚骞剁粡鐢卞唴璐ㄧ綉娌夌Н鍦ㄨ泲鐧戒綋锛圥B锛夊唴锛岃繖涓�绉嶇Н绱繃绋嬬敱ER浼翠荆濡侭iP锛孭DI绛変粙瀵笺�備负浜嗙爺绌惰繖浜涗即渚ｈ泲鐧界殑浣滅敤鍜屽畠浠笌绉嶅瓙璐棌铔嬬櫧绉疮姘村钩鍙樺寲涔嬮棿鐨勮仈绯伙紝浠ヨ儦涔崇壒寮傚惎鍔ㄥ瓙glutelin promoter鍦ㄦ鏍儦涔充腑杩囪〃杈綛ip鍜孭DI銆侾DI杩囪〃杈炬鏍殑琛ㄥ瀷鍜學T宸笉澶氾紝浣咮ip杩囪〃杈炬鏍憟鐜颁笉閫忔槑锛屽叿浣撹〃鍨嬩负绮夎川floury鍜岀毐缂﹕hrink锛岃串钘忚泲鐧藉拰娣�绮夊惈閲忕殑姘村钩閮戒綆浜嶹T銆傛湁瓒ｇ殑鏄紝鍦ㄨ浆鍖栨牚涓紝涓嶅厜鏉ヨ嚜ER鐨凱B-I鏋勫瀷鏀瑰彉锛岃�屼笖杩樹骇鐢熶簡鏂扮殑绫籔B缁撴瀯锛岃缁撴瀯鍖呮嫭BiP锛屽惈璋疯泲鐧界殑楂樼數瀛愬瘑搴﹀熀璐ㄥ拰鍚胺閱囨憾铔嬬櫧鐨勪綆鐢靛瓙瀵嗗害鍩鸿川锛屽苟涓旇繕闄勭潃澶氭牳绯栦綋锛岀爺绌舵帹娴嬭繖绫绘瀯鍨嬪彲鑳藉睘浜嶦R浜х敓鐨凱B-I鐨勮鐢熺墿锛屽畠浜х敓浜庡唴璐ㄧ綉锛屽苟瀵圭瀛愯泲鐧界殑缈昏瘧锛屾姌鍙犲拰浼犻�佹湁鎶戝埗浣滅敤銆�

Seed storage proteins are specifically and highly synthesized during seed maturation and are deposited into protein bodies (PBs) via the endoplasmic reticulum (ER) lumen. The accumulation process is mediated by ER chaperones such as luminal binding protein (BiP) and protein disulfi de isomerase (PDI). To examine the role of ER chaperones and the relationship between ER chaperones and levels of
accumulation of seed storage proteins, we generated transgenic rice plants in which the rice BiP and PDI genes were overexpressed in an endosperm-specifi c manner under the control of the rice seed storage protein glutelin promoter. The seed phenotype of the PDI overexpressing transformant was almost identical to that of the wild type, whereas overexpression of BiP resulted in transgenic rice seed that displayed an opaque phenotype with floury and shrunken features. In the BiP-overexpressing line, the levels of accumulation of seed storage proteins and starch contents were signifi cantly lower compared with the wild type. Interestingly, overproduction of BiP in the endosperm of the transformant not only altered the morphological
structure of ER-derived PB-I, but also generated unusual new PB-like structures composed of a high electron density matrix containing glutelin and BiP and a low electron density matrix containing prolamins. Notably, polysomes were attached around the aberrant PB-like structures, indicating that this aberrant structure is an ER-derived
PB-I derivative. These results suggested that the PB-like structure may be formed in the ER lumen, resulting in inhibition of translation, folding and transport of seed proteins.

Knockout of a starch synthase gene OsSSIIIa/Flo5causes white-core floury endosperm in rice (Oryza sativa L.)
鐮旂┒SSIIIa 鍦ㄩ鏋滄穩绮夊悎鎴愪腑鐨勪綔鐢紝T锛岲NA鎻掑叆绐佸彉浣揻lo5锛�1鍜宖lo5锛�2鐨勮〃鍨嬫槸绮夎川蹇冪櫧锛屼负涓棿閮ㄥ垎鐨勬穩绮変綋鏉炬暎.鍒╃敤X-ray琛嶅皠鍒嗘瀽鍙戠幇flo5娣�绮夌粨鏅跺害鐩稿閲庣敓鍨嬭“閫�锛孌P 30鐨勯暱閾炬垚鍒嗗噺灏戯紝鍚屾椂DP 6 鍒� 8 and涓嶥P 16 鍒� 20鐨勯摼鍨嬩篃鍑忓皯锛屽彧鏈塂P 9 鍒� 15 鍜� DP22 鍒� 29澧炲锛屽埄鐢ㄥ樊閲忔壂鎻忛噺鐑硶DSC锛岀硦鍖栨俯搴﹂檷浣�1锛�5搴︺�傝繘涓�姝ラ槓鏄嶰sSSIIIa/Flo5鍜屽叾浠栧悓绫籗S寮傛瀯浣撳湪娣�绮夊悎鎴愪腑鐨勪綔鐢ㄣ��

To elucidate the role of SSIIIa during starch synthesis in rice (Oryza sativa L.) endosperm, we characterized null mutants of this gene, generated by T-DNA insertions. Scanning electron microscope (SEM) analysis revealed that the starch granules in these mutants are smaller and rounder compared with the wild type controls, and that the mutant
endosperm is characterized by a loosely packed central portion exhibiting a floury-like phenotype. Hence, the OsSSIIIa (Oryza sativa SSIIIa) mutations are referred to as white-core floury endosperm 5-1 (flo5-1) and flo5-2. Based upon their X-ray diffraction patterns, the crystallinity聽endosperm starch, we found that flo5-1 and flo5-2 mutants have reduced the content of long chains with degree of polymerization (DP) 30 or greater compared with the controls. This suggests that OsSSIIIa/Flo5 plays an important role in generating relatively long
chains in rice endosperm. In addition, DP 6 to 8 and DP 16 to 20 appeared to be reduced in endosperm starch of flo5-1 and flo5-2, whereas DP 9 to 15 and DP 22 to 29 were increased in these mutants. By the use of differential scanning calorimetry (DSC), the gelatinization
temperatures of endosperm starch were found to be 1鈥�5 C lower than those of the control. We propose a distinct role for OsSSIIIa/Flo5 and the coordinated action of other SS isoforms during starch synthesis in the seed endosperm of rice.

White-core endosperm floury endosperm-4 in rice is generated by knockout mutations in the C4-type pyruvate orthophosphate dikinase gene (OsPPDKB)

蹇冪櫧琛ㄥ瀷鐨刦lo4姘寸ɑ绐佸彉浣撻�氳繃SEM鍙互鎵弿鍒颁腑蹇冮儴浣嶆澗鏁ｇ殑娣�绮夊紓甯歌В鏋勶紝绐佸彉浣嶇偣鏄疶锛岲NA鎻掑叆缂栫爜涓欓叜閰哥７閰哥洂婵�閰剁殑OsPPDKB鍩哄洜绗簲澶栨樉瀛愪腑锛屾灉瀹炵殑閲嶉噺姣旈噹鐢熷瀷瑕佽交涓�6锛咃紝娣�绮夊惈閲忕浉浼间絾鎬昏泲鐧藉惈閲忓澶氥�傝嚜鑺卞彈绮惧悗10澶㎡sPPDKB鐨勮〃杈鹃兘鏄庢樉澧炲锛屼富瑕佸湪鑳氫钩锛岀硦绮夊眰锛岃儦涓〃杈俱�傜爺绌剁粨鏋滆〃鏄嶱PDKB璋冭妭浜嗛鏋滃彂鑲茶繃绋嬩腑鐨勭⒊浠ｈ阿閫斿緞

We have isolated a floury endosperm-4 (flo4) rice mutant with a floury-white endosperm but a normal outer portion. Scanning electron microscopic analysis revealed that this abnormal endosperm consisted of loosely packed starch granules. The mutant phenotype was generated by T-DNA insertion into the fifth intron of the OsPPDKB gene encoding pyruvate orthophosphate dikinase (PPDK). Plants containing flo4-1 produced no OsPPDKB transcript or the OsPPDKB protein in their developing kernels and leaves. We obtained two additional alleles, flo4-2 and flo4-3, that also showed the same white-core endosperm phenotype. The flo4 kernels weighed about 6% less than wild-type ones. Starch contents in both kernel types were similar, but the total protein content was slightly higher in the mutant kernels. Moreover, lipid contents were significantly increased in the flo4 kernels. Expression analyses demonstrated that the cytosolic mRNA of OsPPDKB was induced in the reproductive organs after pollination, and greatly increased until about 10 days after fertilization. This mRNA was localized mainly in the endosperm, aleurone, and scutellum of the developing kernel. Our results suggest that cytosolic PPDK functions in rice to modulate carbon metabolism during grain filling.

The Rice {alpha}-Amylase Glycoprotein Is Targeted from the Golgi Apparatus through the Secretory Pathway to the Plastids.聽 [涓嬭浇]

姘寸ɑ伪娣�绮夊紓鏋勯叾(AmyI-1)鐨勪簹缁嗚優瀹氫綅锛熻繕鏈夎泲鐧藉湪缁嗚優閲岄潰鐨勮浆杩愰樋鍒嗘硨鍟婏紝濂藉鍥撅紝鎱㈡參鐪嬬湅鍐嶅啓锛屾垜鐪嬫檿浜喡� 锛屾湁璋佹噦鐨勫拰鎴戣涓嬶紵鈥︹��

The well-characterized secretory glycoprotein, rice (Oryza sativa) alpha-amylase isoform I-1 (AmyI-1), was localized within the plastids and proved to be involved in the degradation of starch granules in the organelles of rice cells. In addition, a large portion of transiently expressed AmyI-1 fused to green fluorescent protein (AmyI-1-GFP) colocalized with a simultaneously expressed fluorescent plastid marker in onion (Allium cepa) epidermal cells. The plastid targeting of AmyI-1 was inhibited by both dominant-negative and constitutively active mutants of Arabidopsis thaliana ARF1 and Arabidopsis SAR1, which arrest endoplasmic reticulum-to-Golgi traffic. In cells expressing fluorescent trans-Golgi and plastid markers, these fluorescent markers frequently colocalized when coexpressed with AmyI-1. Three-dimensional time-lapse imaging and electron microscopy of high-pressure frozen/freeze-substituted cells demonstrated that contact of the Golgi-derived membrane vesicles with cargo and subsequent absorption into plastids occur within the cells. The transient expression of a series of C-terminal-truncated AmyI-1-GFP fusion proteins in the onion cell system showed that the region from Trp-301 to Gln-369 is necessary for plastid targeting of AmyI-1. Furthermore, the results obtained by site-directed mutations of Trp-302 and Gly-354, located on the surface and on opposite sides of the AmyI-1 protein, suggest that multiple surface regions are necessary for plastid targeting. Thus, Golgi-to-plastid traffic appears to be involved in the transport of glycoproteins to plastids and plastid targeting seems to be accomplished in a sorting signal-dependent manner.